383 SHOOTOUT-GEN 1 SBC VS GEN 3 LS (CAN THE OG COMPETE?)

[@taylorswiftnumberon1]

I think for most it comes down to cost and ease of installation. I bought a skip white internal balance 383 kit. machine shop double checked specs and was spot on. dug in my junk pile came out with a block. Mike Jones custom grind roller. Profiler 195 heads, Vic jr and quick fuel 750 carb… dropped into 85 c10…no fears, no tears and no hassles in just a few hours…535 hp at 6300 rpm all for less than $6000… hard to beat that with a stick.

[@masonite1973]

LS are pretty cheap too

[@BillieWilliams-l6m]

You are so smart

[@edwardpate6128]

I will always have a soft place in my heart for the original SBC.

[@BDauto86]

I'm a fan of the LS stuff but I also have sbc 350 and 400. There both cheap and easy to work on and can make good power.

[@b.c4066]

Dollar for dollar it's still hard to beat it for power produced on a build. Junkyard engines don't count, if building from scratch the sbc is still king of cheap reliable power. Most lose sight of that. When the junk supplies dry up the ls won't be so cheap to get and build.

[@BDauto86]

@@b.c4066 I agree and while the LS prices are climbing the sbc prices are dropping and availability going up. Quick search on marketplace I can find 20sbc for cheap within 40miles.

[@albertgaspar627]

@@BDauto86 agreed on all points. I picked up an Olds 455 with an engle cam and headers and 442 cast iron intake from a kid who wanted an LS--paid $150 for it dissassembled. the LS shadow is spreading to other engines :) I also picked up a Victor intake for the Gen One at a tag sale for $10--no way i'm finding a used LS carb intake anywhere for less than three digits.

[@badgerbait8351]

Dang right!

[@hgwaterous]

When I was 16 and building my first motor, my machinist said, "Always spend money on the best heads you can afford."

[@andrewslagle1974]

you got it sbc power is maid in the heads

[@Floordford]

Those old heads were the biggest choke point.

[@bri-manhunter2654]

Agree, but you need a proper cam to take advantage of the head flow.

[@glennmanchester5335]

Yeah the cam but with good heads you can get equal power w less cam so

[@fuddrucker74]

@@glennmanchester5335 and its much easier to swap cars then buy new heads and polish/port them. Heads first. Get them sussed out including locks/springs/retainers/springs, and then figure what profile cam you want to compliment what your heads can flow.

[@hawkdsl]

SBC fan for sure. But, I'll LS swap the world if I could... keeping a few SBC just for fun. What is lost in the comments is why the LS is far, far superior to the SBC... Giant cam journals. 6 bolt mains. Heads. The LS may be the last time a giant manufacture designed and built a nearly perfect and ridiculously reliable engine.

[@andrewlanger2168]

What I love about modern V8's is they basically sold souped up performance engines with tiny cams in them instead of the choked down V8's of the past.

[@hawkdsl]

@@andrewlanger2168 pretty much !

[@swa99surffin]

You ls swapp my 86 monte

[@hawkdsl]

@@swa99surffin sell it if your too lazy

[@swa99surffin]

@@hawkdsl ha im not i was being sarcastic an i dont know how to install a engine

[@ChrisH930S]

I used to run a 383 SBC in super gas, we used a different combination. A 400ci block and a 350 crank using the large brodix heads, single 850 carb, more radical lunati cam. We made 675 hp on the dyno. I think the difference you’re seeing is in the intake/cam

[@rjames5111]

you're pretty close. He also forgot to mention the cam shaft lift for sbc was .585 while the LS was over .600. That makes a huge difference. Give the SBC a .600+ camshaft and watch how close the numbers are.

[@jeffrey4547]

i have a large journal 350 and a 400 but one problem the 400 is in a 79 short box 4x4 100% factory truck full option with only 35,000 miles on it in mint condition but then again i have a few 450 hp 454 sitting with low miles

[@kregbelcastro2749]

I'm interested in your combo can you give me a few more details. I run a 385 stroker on my airboat but was thinking of building a 418 stroker

[@jeffrey4547]

@@kregbelcastro2749 u really think i would part out a low mile 79 4x4 that is in mint condition u can buy the whole thing for about 35,000 then i will sell it just because i got it free i will not let it go cheap but u can get 450 hp 454 with 4 inch stroke out of motor homes and they come with a 02xx trans good to 800 hp i got 4 setups sitting right now

[@kregbelcastro2749]

@@jeffrey4547 sorry the message I sent was for Chris H I wanted to know more about his 383 that made 675hp Jeffery I already have a 514hp 383 so i don't need your truck

[@danielj3230]

Ls deck height is 3/8 of an inch taller than sbc. This enables shallower valve angles and a better flow towards the valves. This is probably the single most important difference in power potential

[@michaelburrell4685]

Since there is no equivalent EFI intake manifold for the SBC, why not run the test with a single plane intake manifold and the same carburetor on the LS? That’s as close to apples to apples as it can get.

[@totensiebush]

I think he's trying to run the best available intake in both cases, rather than limiting one to the ability of the other. If you wanted apples to apples, you'd limit the SBC to running the same valve sizes the LS has. That would be BS too. I think valve angle is likely a lot of it.

[@dougj.8288]

I think the valve angle was a big part, could have even done the 18 degree head to make it a little closer but, I think EFI could have also played a part in that those numbers also.

[@totensiebush]

@@dougj.8288 when Richard runs apples to apples carb vs EFI, carb almost always makes a bit more power. I think it's more the intake than the EFI, but you can't run that style intake with a carb.

[@danieldimitri6133]

@@dougj.8288 yes, despite the equal flow the 23degree head is just kinda wonky. The valves arent centered in the bore and the pushrod pinch changes the cross section not to mention the gen1s 5th head bolt between the ports. You can make power despite these things but if the port dances around bolts and pushrods what cross section changes have to happen to make it happen and how does that change the acoustics of the port, static flow is one thing but an intake is a dynamic system with sound waves and intermittent flow.

[@dougj.8288]

I know the carb usually makes more peak power but it wouldn’t have been an issue to slap Holley EFI on that intake or swap the intake on the LS and run the same carb on both.

[@holgateperformance4250]

It’s a few things. Valve angle is huge but there is more to be said about the difference in stroke and the way it fills the cylinder as well as rod length to stroke ratios, camshaft selection and the entire combination in general. There are far more differences in these engines than similarities. Love watching your videos! Thanks

[@oddmanout7755]

Agree, the majority of the power difference is in valve angle and cam.

[@milojanis4901]

Are you guys aware World Products offers a traditional SBC block, but with an LS, 4 head bolt deck, which allows the SBC block to run LS heads.

[@marcalampi5036]

I'm glad you mentioned this great combo ​@@milojanis4901

[@Nanaki1422]

I don't think this question will ever be answered. How about 427 big block vs 427 LS vs 427 small block.

[@vettesrule3170]

Absolutely! What I mention above needs to be addressed as well. Same ring pack widths, piston, and rod weights at least as close as possible with like materials. No titanium rods and as similar designed heads as possible. 1 CNC'd, ALL CNC'd. The 427LS and the 427 SBC gen 1 would be the most interesting based on same bore and stroke if internals are similar and the style of induction is at least similar, IMHO.

[@brokedonkeygarage6017]

Years ago I think it was car craft did 408 sm blk vs 408 BB. LS where not around yet . The bb stomped the small block and they where actually very similar builds .

[@mikeeaton9822]

I think I remember the CarCraft article the BBC made so much lo-end torque that the SBC PUT UP THE WHITE FLAG TO SURRENDER LOL!!!!

[@shadvan9494]

@Broke Donkey Garage, Hot rod magazine also ran that same test with a 408 big block vs 408 small block back in 98. the LS had only been out about 2 years. it was called Rodent Rumble. www.hotrod.com/articles/hrdp-9808-chevrolet-engine-block-challenge/ they even used "the same" cam. it was a Comp Extreme Energy 284, the lobe profiles and LSA are identical on both the big block version and the small block version of the XE284. They tested them at the dyno and the drag strip in the same second gen Camaro. The Big Block won both hands down. I am pretty sure the BBC would beat the LS as well in the same if the test was conducted today with the LS included. to quote Steve Brule "Nothing Beats and LS... Except a Big Block Chevy"

[@brokedonkeygarage6017]

@@shadvan9494 that was the one I meant . Thanks for the reply .

[@chuckmarlin6192]

I have to think that the difference in valve angle will allow the LS to have more tumble, a straighter flow path, and more mixture motion. That being said, the intake on the LS is superior. You could try a carb and single plane intake on the LS to see just how much of a difference that intake design is worth.

[@HauntedBranch]

Yes I would like to see a carb and single plane intake on the LS

[@jcoats1203]

Excellent comment.

[@dustysilvers7115]

It’s all about the 13• head and the intake. I love sbc but the LS is no doubt a lot more efficient

[@kennethcohagen3539]

Hey Richard, the guys at west tec screwed together two 383’s a while back. They made them as close to each other as possible. One was an SBC, the other was a 383 Mopar. For those who don’t know, the SBC is a motor put together with parts from two engines. A 350 block gets a 400 crank. You get a 4” bore with a 3.75” stroke. The Mopar is a factory built motor, 4.25” bore with a short stroke of 3.38”. Like I said, both motors had the same static compression, cam, and intake design. The biggest difference in the two mills was the rod length to stroke ratio. A piss poor 1.52-1 for the SBC, 1.88-1 for the Mopar. Then they ran on their Dino, back to back only to get nearly identical torque and HP. I though going ti to this one, as did Friebuger and the Steve’s that the SBC would have it all over the Mopar in the torque department, while the Mopar would make more hp because of its ability to rev. Now, I’ll be watching this one very closely to see what happens. So why don’t you take the winner and put it up against Thierry motors to see which one is the best 383! I’d love to see that. P.S., I’m still waiting to see a well built AMC dyno’d somewhere. Let me know if you decide to do that one and I’ll point you in the right direction. I built engine for 20 yrs, then moved on into electronic Engineer for Intel, and I sure miss my engine building days!

[@joshgessinger4509]

Id say whatevers more practical to build is the best answer. If u have a small block chevy already just use what u have. Or if ur shopping for blocks look for the best deal. Whats going to be easier to swap. Iv owned small blocks and LS’s. My favorite engine was a 358 small block in my 79 Camaro my first car. Loved that car the engine was just awesome wish i never sold the car.

[@michaelhonea7407]

Put a carb on the LS and find out if it is the intake/fuel injection.

[@SealofPerfection]

Yep. Or put a good EFI system on the SBC and see how it does.

[@pyrorye-80]

Fuel injection is great for driveability. Doesnt necessarily produce more powerthan a carb.

[@SealofPerfection]

@@pyrorye-80 Direct injection does. Your "carb looking" EFI's, no, they don't. You're right.

[@davidcunningham00]

@@pyrorye-80 you can tune better and that can be worth 30 hp difference

[@johnbeverly1653]

I would like to see the numbers with a carb on the ls , I think they would be higher

[@davidburgner5826]

I'll always be an old school SBC guy. They're legendary. But the LS heads flow so good and you can run a huge cam and still be driveabile... The LS is better but not dramatically considering the 50+ years difference in them. I love both and always will.

[@patrickmoore1017]

I would run a different cam in the SBC. 106 LSA, 102 ICL, 1.6/1.5 rockers intake/exhaust, 280/280 duration at .006" lift, 235 ish at .050", 68 degrees of overlap. This will put you right on top of the LS. Also, I would port that intake to bring it up to par.

[@Supercharged287SOHC]

The LSA is to low on the cam to keep the powerband up , 112 LSA is minimum

[@benkrom2737]

Just the configuration of the oil pump and not having a distributor will give the LS an advantage. Cathedral ports on LS is another plus and LS block is skirted with 6 bolt mains and all are roller cams. Tolerances can be held better on the LS. All this makes more hp, but I still enjoy a healthy SBC that has been around since 1955, never gets old !

[@z6Coupe]

It's nice to see that a well built small block with the same cubic inches can compete with LS style engine. I would say that the combination of sequential EFI and coil on plug ignition are why the numbers on these builds weren't more similar. Give the small block those upgrades and watch it do work.

[@Thumper68]

Carb will make more power then fuel injection and they are getting plenty of spark with distributor. The ls flows more air is all.

[@bizzybeast6522]

@@Thumper68 naw I think he got a point fuel injection brings instant power that carb gonna dump gas and the motor gone catch up

[@Thumper68]

@@bizzybeast6522 it wasn’t really a suggestion I know I’m correct the ls heads flow a lot more air that’s why it makes more power

[@johnkrucar2119]

@Thumper I definitely think it's the fuel injection and coil packs! But also believe the heads on the ls are better

[@jlarocque84]

@@johnkrucar2119 it's the cams you can't compare power with different lift on the cams obviously the cam with more lift will make more power.

[@garyvancamp5452]

👍 SBC 383 ~ gear jamm'in ground pounding street motor on the cheap ! 😊 Been around for ever, reliable ~ with a good set of heads plenty of power for most people.

[@jamesandannschmitt6835]

Valve angle and port energy explains cam requirements. The intake differences on you test pieces would explain the rest.

[@stewarth8390]

Exactly what I was thinking too! Put a single plain and carb on the LS or put say a Holley sniper Efi on them both and I think the gap might be closer between them.

[@frankrizzo2724]

I've heard of port velocity and flow. What are you referring to as far as port energy?

[@jamesandannschmitt6835]

@@frankrizzo2724 as I understand it; it has to do with flow and velocity and the length of the port. If you have a smaller cross section area at a certain length that flows equally to a larger cross section port of the same area you see the velocity higher. What is difficult to measure is how the pulsing or pressure waves affect things. David Vizard has a way of explaining it. Check out power tech 10 videos. I am pretty sure he would do a better job of explaining it than I can.

[@frankrizzo2724]

@@jamesandannschmitt6835 I've read alot of visard's stuff. Really like the way he always uses a tight LSA on his cams. I'll have to check that out. Thanks.

[@horsefly1020]

@@stewarth8390 a carb on a LS engine makes more power then EFI

[@davidwitcher5443]

I'd like to see cost per engine to replicate.

[@mikelewis5900]

That would be a big difference

[@tdalb8985]

That is a good question, but I suspect it's getting close to even.

[@frankdatank7751]

Sbc is a bigger bang for the buck, 383 is $800 for sbc compare to 2k ls stroker.

[@davidwitcher5443]

@@frankdatank7751 Yep. I found it to be $2400 for the LS 383 rotating assembly. Must be the reason everyone slaps a turbo on them.

[@ryanrobinson130]

The ls would likely be cheaper.

[@stevenwhite7839]

Hi, the only equivalent SBC intake to a Fast LS is a street tunnel ram. That's the cost of running a SBC. Steve

[@pisstoffcat5136]

Didn't mention cranks and rotating assembly, I once built a super light crankshaft 383 from lunati , compared to an almost identical motor with a eagle kit in it, was apples to oranges, revved higher and had lots of torque, I'm suspecting the ls has a much lighter rotating assembly.

[@Logan1-p69]

My thoughts. The 4" stroke on the ls is what beats the conventional 383 on the low end for torque. Then on the upper end the 13 degree heads take over and out performed the 23 degree headed SBC. The Ls is just doing it more efficiently. Now change the Old SBC to 18 degree heads and they may even out or the old SBC may take over on the top end.

[@causeimbatmaaan]

Well you're wrong about the 4" stroke for low end torque. Long stroke for torque is a myth people just can't get over; too lazy to think it through or something...

[@jradish]

@@causeimbatmaaan that's correct, stroke is only one part of the equation but the things that affect torque much more are cam timing cylinder heads and compression

[@anonymousbrown]

Try building a 3.75" stroke version in a 6.0 block and see how it would compare. I'm thinking same bore and stroke between the 2 engines.

[@RyanSteele92]

A 383 is basically a 6.0 do at 383 SBC vs a camed 6.0 lq9

[@horsefly1020]

6.0 is 366 far from 383

[@causeimbatmaaan]

@@horsefly1020 377 would be a much better comparison for valve clearance and flow.

[@sideswiped6874]

you like suggestions; how about building a 600 HP Chevy 376 stroker (3.750 stroke 4" bore) and a 2nd Chevy 377 short stroke (3.480 stroke 4.155 bore). use the same cam, same heads, same intake/carb/headers in both engines. and dyno both

[@LordMekanicus]

What you have to take into account is the airflow in the mid-lift. Both valves spend more time in transit than they do full open. What's the flow at 450 lift on both? What's the turbulent flow like in the valve curtain? How shrouded are the valves both in the chamber and on the deck? Old style sbc engines seem to benefit most from longer duration and higher overlap than they do high lift. (This coming from years spent on a scratch-built flow bench and the ire of many a mustang guy trying to say we were cheating.) But then again, our goal was to optimize for mid range on engines of five liters, although we have since discovered the same principals apply shockingly well to even the 400 sbc. The 383 is a bit of an odd duck however. The bore to stroke ratio sounds great on paper in comparison to even the 283, but the application seems to be more suited for high rpm, constant speed, or boosted applications. In a way, its like asking a Meyer-Drake to make peak at half redline, and a model T to make peak at twice redline. The LS seems to have a more usable bore/stroke for mid range.

[@sretienne]

.625 vs .585 lift (do I have that right?) seems like a significant and obvious difference.

[@shadetreetrades.jackofall2188]

Intake on LS is better and maybe the ring package being thinner on LS. Between those two things, would make up that difference. And maybe the tiny higher lift cam and angle on the LS. But if you did that hybrid world products block that can take LS heads and intake. That would be a great comparison. They have an episode of it on hotrod tV. It’s pretty cool allows you to use a regular sbc architecture and engine mounts and crank, but allows LS piston and rods and heads to be bolted on. That’s the engine I’d build if I could. Best of both worlds.

[@BlakeBarrett]

At what point does the question turn into “Which setup has the best volumetric efficiency?” I’m also going to have to agree with the others who have said valve angle and intake manifolds.

[@jackhelm92968]

Agree!

[@Hamchunk1968]

Yeah, somewhere back in my deep prehistoric memory, volumetric efficiency comes to mind. Air flow, swept area, how fast the cylinders are filled and evacuated, stuff like that. I never dove too deep into this, but I remember it coming up.

[@theotherevansmith]

I think even in an apples to apples comparison, the LS has better VE. I love the old SBC, but the LS beats it every time

[@grandnattygarage7355]

I think if you ran a hydraulic roller cam with identical lift, duration and Lsa, you’d have a more fair playing field. LS might still be ahead but the gap would close dramatically. Also that very minuscule amount of compression makes a difference. The closer you make all the specs on each engine, the close the power numbers will get. If they both had identical specs, it would be extremely close. Possibly not enough to even notice when driving. Nice video!

[@nashvilleoutlaw]

I believe it's a combination of many little improvements. Fuel injection for a more even fuel charge in all cylinders, valve angles, thinner piston ring pack, reverse flow cooling, tighter bearing tolerances, shaft vs pedestal mount rockers, firing order.

[@blueridgemountainprepper2166]

I think your answer is clear or to me. Do same test but put Brodix 13 degree head on the Gen 1 383 and the LS will be left behind. Try it...

[@danielwoodard680]

I admire how you pump out facts and we all go crazy figuring how disagree with objective truth. Please tell us why our opinions should keep changing when the truth shows they must

[@xlr8r3VA]

You hit the nail on the head Richard! It is all about the valve angle. Why do you think professional racers run 15 deg and smaller valve angle heads? They flow better in the upper rpm range. This is why a Ford 302 can compete with a 350 Chevy, you have a 20 deg valve angle vs a 23. Put a set of 15 degree heads on that 350, and watch what happens to the power!

[@causeimbatmaaan]

Uhhhh, no lol

[@bobdobalina8910]

Would it be the Fuel Injection delivery system? The LS is more precise = Better fuel atomization & a more complete combustion cycle. Electronically metered versus just dumping ever increasing amounts of RAW fuel in. Perhaps the stroke would also play a factor, longer stroke more charge, less area = more power. per sq inch/millimeter. Still, none the less, those are very impressive numbers for either stout motor combination.

[@bcbloc02]

I think most of the difference comes from the intake manifolds. That much longer runner on that fast is far superior to the single plane of the SBC and would contribute to across the board power gains below 6000rpm.

[@jimmy_olds]

Would’ve been interesting to see an RPM air gap on the SBC, especially down low

[@Thumper68]

It would have gains down low of course

[@davejalenderki]

I am about to build a 383 and the intake I’ve chosen is an air gap intake with a Holley Sniper everything from in tank fuel pump to the ignition system. 1.6:1 roller rockers and I am probably going to ditch the hyd cam and go with a roller. Can’t wait…

[@JacobLAChristenson]

I'm going with the intake. I've watched Engine Masters and they have had various intake shoot outs and you would be amazed at just changing a manifold would do. I'd recommend getting a Brodix matched intake. Watch the big block intake shoot out I think its season 5. Also the cam profiles I think might play a role in it to.

[@bdugle1]

The characteristic torque curve is due to “long runner” FAST intake vs a single plane carb intake. The horsepower increase with 14° less intake lobe (and the actual level of the torque curve) is probably due to flow dynamics not shown in the steady state number from a flow bench. Someone mentioned port energy, something Vizard quantifies in his head analysis. The different valve angle just works better on the LS.

[@rattdog777]

😱

[@Lezanator9]

Love this, have you heard anything on the factory L8T crankshaft being used in LS Motors? 3.86” stroke and if I’ve researched correctly the pistons can be used from a 4” stroker kit with 6.2” rods. The cam gear has to be swapped out but I can find these cranks for ~$300 used in my area.

[@gernblanstien4968]

rod angle? ring thickness ,tension? / larger cam core allowing more desirable ramping? / rotating mass? Then add the valve angle, injection, etc... MAYBE THE LS HAD A CHROME DIP STICK...

[@albertorodriguez6661]

I like watching what you guys do but when I see bone headed stuff I have to point it out You guys should've ran a carb on the LS or vise versa run the fuel injection on the sbc 383 then we would see better results and try to use indentical brands heads,cam,and intake oh and compression as well on both engines then we can see the real competition like they both had different heads cam and induction 🤷sorry. Hey but I still love watching

[@jonathandye2812]

My theory is because of the inconsistency in intake and exhaust spacing on SBC combined with older stying manifolds and fueling. Idk like to see this comparison with more comparable cams and then the Edelbrock Pro Flo4 sequential port injection with the top mounted throttle and then with the tunnel ram style too. Also the bore and stroke differences make a difference too, even though they are the same cubes, having different strokes means piston speeds greatly differ and effect top end HP.

[@mannybarreda1390]

I think the valve angle will account for the need of greater cam timing. As for the horse power difference, I believe that is attributed to the slightly longer stroke of the LS allowing for greater cylinder volume / air velocity that will use the cylinder head to a greater extent.

[@markwallace5274]

I say valve angle and stroke even though the LS was equipped with a smaller bore with its 4” stroke it was able to take advantage of the head flow numbers and fill the cylinder more efficiently my guess is if RPM continued to increase the HP gap would’ve gotten smaller between these 2 engines.

[@scottleggejr]

Ya agree. VE / scavenging are going to be way better on the LS. He didn't mention ignition timing, but I am guessing the LS needed a lot less total timing to hit those numbers too.

[@renwickconolly2839]

I agree..valve angle..and also the Fast long tube INTAKE MANUFOLD..

[@joescabarozi423]

a few things are contributing: the head flow is advertised (in the video) as a similar single value, but the valve angle of the LS heads are allowing more area under the curve, along with not insignificant lift increase. the long runners of the truck manifold are also providing a torque increase throughout the curve. There are probably some frictional losses in the ring pack as well on the older motor. the SBC 383 cam is probably not as well matched and the valvetrain is likely heavier overall, especially with the bigger cam timing events.

[@richardmoe666]

1st I would like to say thanks for what you do! I love all the videos. Always informational, best from Wyoming.

[@Sean_Farmer]

My suspicion is that if you had a pair of 18 degree heads and an EFI setup on the SBC you would see a huge difference. Of course you would then have to have a pair of LS heads that are going to be comparable in valve size to try and eliminate that variable.

[@tonkatoytruck]

The 13 degree head does a great job to unshroud the valves for better flow over a wider flow range. And aren't the catherdral port heights higher on ls heads for more direct flow to the valve? The LS heads also have a much better combustion chamber design, better exhaust flow, and better spark plug placement. P.S You have built an LS 383 with 600fhp+, 640+ seems feasible on E-85 and 13:1 and still run a hydraulic lifter. And its hard to beat the LS style intakes like FAST so without more cam and compression, running hi rise intakes probably was not going to buy you much. I think you did a great job making it a fair comparison.

[@C6Z_Bob]

I'm guessing it's intake runner length and better port velocity on the LS.

[@firebirdjone]

First thing that popped in my head before I clicked the video was the big difference in valve angles from Gen 1 SBC to the LS. The LS has always had an advantage there, and I've found they never really need much camshaft to make good power. I attribute that to a pretty good cylinder head with advantageous valve angles. The Trick Flow takes that further with 13.5 degrees vs a stock LS 15 degree. Maybe compare a gen1 SBC with a set of 18 degree heads and see if the difference is closer? Starts to get pretty expensive though.

[@brendanmccarthy492]

Afr sells good heads for sbc I have one on my 355. And it’s awesome. Factory comes Cnc ported. With a mild cam you’ll definitely wake up that sbc.

[@blarson8111]

My thoughts also on the advantages of the flat 13.5°. The whole head was a clean sheet and every little detail counts. Ol reliable sbc heads designed back in early 50's.

[@daviddavids3468]

OH MAN I WOULD LOVE TO SEE A 383 SBC WITH TRICK FLOW 18 DEGREE HEADS , 1,6 ROCKERS , A 2 INCH CARB SPACER , SHE BE A 100 HORSEPOWER MORE THAN THAT LS !

[@danieldimitri6133]

In my other comment i speculated on vibrations and manifold design. It could also be port limiting velocity on the pushrod pinch. While david vizard obsesses about cd in the port you can be so efficient that the cfm is fine for your application but you can still indicate that the port velocity is too high at the pushrod pinch. Its difficult to get this area up to 2.0 insq which youll need if not more for a high revving 383 or a 400. Some heads might only measure 1.7sqin inside the pinch. Many people seem to think its enough to measure the gasket flange or calculate the average cs from cc and length but you cant get air to go supersonic even if its only temporary. So on bigger cuin small blocks or high revvers it should be beneficial to open the pushrod pinch no matter its negative effects on cd.

[@trevermonk8575]

Time to build a 13 degree 383 sbc lol. I am sure you hit the nail on the head. Valve angle and intake design.

[@johnsheetz6639]

I really do like the LS but that small block Chevy sound is the heartbeat of America.

[@ramseycattn5941]

My thoughts on why LS did better with much less cam duration: 1. Low lift numbers on LS head were likely a bit better. 2. Bigger base circle on LS cam allows for much more aggressive ramp rates. IE you can get as much air flow with less duration because the valves are at a higher lift for any given spot on the cam profile.

[@yurimodin7333]

also IIRC an LS has 1.7 rockers from the factory.......most of the difference probobly comes down to valve angle and the port designs inherent to each design.

[@michaelallen2501]

I'd like to see a 383 LT1/LT4 battling the LS. With the stock manifold, albeit ported, and with the Edelbrock "LT4" manifold. Running on Holley EFI. AFR has some big boy LT1/LT4 heads ;-)

[@Washington5057]

I'll go with valve angle, the tenth in compression and more cam lift with the LS... All 3 of those things cumulatively make the difference. I'll also argue that the SBC camshaft didn't have the development correct for the application and the longer stroke of the LS made it more efficient pumping the intake and exhaust cycles with its cam events. I still subscribe to connecting rod ratio effecting piston dwell, position and relationships to cam events. But the chief difference is the cam selection and valve angle in the head.

[@daviddavids3468]

LS HAS A LITTLE BIGGER CAM YES, BUT IM PRETTY SURE ITS ALSO GOT ATLEAST 1.6 ROCKERS TOO , THAT MAKES THE LS LIFT QUITE A BIT BIGGER ! SBC TORQUE IS LOW BECAUSE INTAKE RUNNERS ARE TOO BIG ! EVEN AFR 195'S WOULD MAKE ATLEAST THE SAME POWER AND 50 MORE TORQUE

[@stonebreaker984]

The LS manifold is a tunnel ram manifold folded up into compact package. To do a true apples to apples comparo, you would need to do a SBC tunnel ram compared to an LS manifold.

[@WhyNot6243]

It would be interesting to do a test with as close as possible valve angles, similar style/length intake manifolds, and same firing order. Either the 4,7 and 2,3 swap on the sbc, or making a sbc firing order cam for the LS. It’s most likely a combination of all the little technological improvements combined.

[@tatehoward8678]

You would also need different position sensors

[@jlarocque84]

If you put a .585 lift cam in the ls to match the sbc the power out puts would be almost identical

[@jaydubb71]

Heads. Period. 18 degree SBC heads would have made the test more comparable.

[@robertelmo7736]

Yep, it's the heads. Those LS heads are great performers.

[@KingJT80]

yeah 18 degree brodix heads would have probably been over 550+ even an AFR 195 comp probably cost the same as those trick flow cathedral ports and those world have probably made 550.

[@KingJT80]

also look at this combo. smaller ports and smaller hydro roller cam but its an AFR with an air gap intake made 557HP kzbin.info/www/bejne/nYa8q5Sko6droK8

[@docsmallblock6584]

@@KingJT80 better yet, 15 degree profiler air strike heads! And I guarantee you that the gen 1 out performs the Ls! Not that I'm knocking an Ls by no means, it's a proven excellent platform for sure! But for ease of install and operation, you simply cannot beat the gen 1 sbc!

[@KingJT80]

@@docsmallblock6584 yeah no it's great stock as proven by this video made at least 40+ hpmover the vortex 350 vs a 5.3 truck engine with a truck intake I just tell people if you're not gonna turbo it just use a 383 if you already have the header etc

[@Michael_Lorenson]

What strikes me is how the close the ancient SBC comes to matching the LS. For my SBC 1988 Corvette, I'll modify the SBC rather than do an LS swap. I'll give up a theoretical 10% power difference to avoid all the hassles of a swap. In fact, before I'd do a swap, I'd go to forced-induction on the SBC. No way I'll ever need more power than I can get from that.

[@moabman6803]

Ls has more advantages than just power. The block design is way stronger. Also the seal and gasket designs are more reliable so you don't have oil leaks.

[@Packer1290]

Ported heads on the SBC would have closed the gap even more.

[@Bman_1974]

@@moabman6803 the ls isnt everyones taste of engine

[@Texasmule]

​@@moabman6803 🧢 sbc has a stronger block

[@moabman6803]

@@Texasmule LS has 6 bolt mains. Sbc block is not stronger.

[@pablojanski.2559]

Richard.. as a note and a thought. I have seen sbc pick up power with coil per cylinder ignition setups. Might be a good test idea for you..

[@242bleek]

I think the LS should have had a carb and single plane for this test and the sbc should have had coil on plug ignition and at least 1.6 rockers like everyone runs on them. The LS still has some advantages but that might have narrowed the gap some more.

[@jamesfowler7065]

I think line of sight is much better on the LS. Any time you improve the approach angle to the back of the valve, it means more power carried longer and higher in the rpm range. All you have to do to see what im talking about is look down the injector bodies with wide open throttle, on a modern Japanese motorcycle engine. Radical cams dont seem to interrupt low speed power assuming a proper tune. The closer we get to these designs in automotive engines the more power we will produce.

[@kennethpowers8995]

Typically out of two engines with the same displacement where both have very good head flow and proper valve event timing I would expect the engine with the larger bore to edge out and make more power. This is why for example I like the 4” stroke 427 LS engines because they have a large bore and Breath very well when the right parts are used up top. I’ve never been able to really figure a definite reason why the Ls put powers a SBC though especially when the SBC in question benefits from a larger bore, and can use big valve heads. I know the valve angle itself comes into play with cylinder filling, but even on engines other than 23* small blocks and 15*/18* LS engines the LS typically makes more power than the SBC when similarly equipped so I really can’t pin it down entirely.

[@jamesrogers5783]

heads and valve angle for the LS . you could do a carbed LS with a super victor --to sort of even the intakes out.

[@mrmatt3093]

Bigger cam in the ls utilizing more cfm accompanied with the 13 degree vs 23

[@DodgyBrothersEngineering]

way smaller cam in the LS you mean...

[@richardholdener1727]

LOTS OF GUYS ONLY LOOK AT LIFT!

[@matthewstansbury3047]

@@richardholdener1727 realistically the cam in the ls is more “heavy hitting”. 625 lift on a what was it 230something intake lobe profile is WAY sharper of a lobe than the .585 at like 242 on the SBC. From my months and months of observation of builds and cams. Torque comes from port velocity more than anything. That’s the same reason why those hogged out POS eBay heads that are like a 235cc intake runner don’t make good power. Simply being it lacks the VELOCITY. On a boosted build/super high revving engine or bigger than 400cube/4”bore they would work fine. This is also a small part of many reasons why big cams make less low end power than small cams. Now if you could get the big lift out of the big cam on the same lobe as the small cam you’d make more low end torque than the smaller cam, more peak, and be able to carry the power a little further out. the reason you don’t see this pretty much ever is the lifters and valve train. Say you put a .630 lift on a 222 duration lobe, lol that lifter is going to be like a bicyclist hitting a Boulder in the road vs a going over a speedbump. There’s much more than lift and duration in cams, different lobe types, valve events, and ramp rates greatly effect how a cam performs and also how much abuse it will put on your valve train. This video to me shows you this, the bigger lift and smaller lobe helps snap the valve open further and also faster as it has a much faster ramp rate(PORT VELOCITY)and the nice 220 intake runner on the trick flow isn’t too big for the displacement and works nicely to keep port velocity up in mid range then at higher rpm where engines start to run out of breath the bigger lift helps feed the engine a little more than holding the valve open a little bit longer but really the high end is very likely to be from that fast 102. I have a heads, cam build and I’m pulling vacuum on an ls6 intake at around 5k and up. The heads and fast are what’s making that ls shine above 5500rpm.

[@jeffcraven2437]

I would like to see exact same cams and exact same rocker ratios with only difference being the degrees of the heads. Same carb, same style intake.

[@matthewstansbury3047]

@@jeffcraven2437 imo one of the biggest perks of the less valve degrees is ability to run bigger lifts/durations without PTV issues. Don’t hold me on it, but also helps utilize the sweep styled rocker arms at higher lifts which IMO are leaps and bounds better than a roller style when it comes to valvetrain stability. The only ones I would recommend on an LS are the texas speed ones. They are the only ones I know of that don’t weigh a ton. Those heavy rollers just make under your valve cover look pretty and just add to chances of valve float.

[@irocman311]

Love your content, and this is a better comparison than any others I've seen But it seems the old school stuff is always mismatched. 225cc intake head on a small 383. They may flow 300 but not until .600+ lift (cam is under that). Put a set of afr 210 race/profilers, something that flows 300 at ur cam lift and you'll be closer. (Proven combos). 4.0 bore based LS would be a fairer match with similar cam profiles, along with both EFI based CNP.

[@mistersniffer6838]

Thats what I was hoping for, but, I guess I will have to take what I can get :/

[@carterscustom.1309]

It’s the computer controlled fuel and spark system. They make a kit that allows ls heads to bolt on a sbc. I’d try that out and see what happens

[@jackhelm92968]

I believe the difference is in the SBC 23 degree heads vs the LS 13 degree heads. The next best test is to put a good set of 12 degree heads with 1.72:1 roller rockers installed on the 383 SBC and dyno it. I believe it’s a flow EFFICIENCY advantage that the LS has. Just my opinion…

[@drivinwithdrew7676]

The small block with a good single plane would probably put up a little better fight imo, my 383 stroker has 11.0 compression, AFR 210 head, strip dominator intake, 243/249 solid roller, and according to air flow and fuel consumption, it makes about 50 hp more than my 370 11.0 compression ls with a 231/243 cam and fast 92, ported 706s

[@derekvanvalen7362]

706 heads are the reason...

[@DudeManRife]

I’m no expert by any means, but I think there’s a few factors mainly at play here: 1) Slightly under square engines are more efficient bcuz the flame front can fill the combustion chamber quicker 2) A 10 degree difference in valve angle 3) Larger camshaft core size in the LS, meaning there may be less pressure on the lifters (side loading) and camshaft from the valve springs pressing up against the rocker arms. This may be negated by the fact that LS run 1.7 ratio rockers vs SBC 1.5 ratio

[@sixx6sixx107]

World has an old skool block that fits the LS top end...would love to see an all out N/A shootout between the three...same compression,same stroke and bore, same head degree angle, and 750cfm carb for the three combos and see who comes out on top 🤷🏾‍♂️

[@nightrider327]

It's a few things. 1) The valve angle. 2) Port shape of heads/intake. The tall skinny LS port has a high port velocity. 3) Rotational weight. 4) Friction. The LS uses the smaller 3mm/1.5mm ring pack, plus a few other "low friction" design ideas.

[@SonicRacingEPt]

I'd say maybe the square vs over-square would have something to do with it making more top end power? Also if the SBC 383 had en efi system to be able to "fine tune" the induction I'd say it would gain some power in that aspect too and also the angle of the SBC valves angle closer to the LS angle would also gain it some power closer to the LS as that air/fuel mixture would just tumble right down the intake port to make it a better contender as well... Gotta make that SBC EFI Richard see what it does iron that air/fuel mixture real crisp ??

[@roachwerks3043]

The scrap yards around me have LS motors pulled out before the stuff even makes it to the public. I have a feeling some of the eBay sellers have some kind of deal with them. But you can find old school and vortec motors all over the place

[@doranmaxwell1755]

Having done 327 chevy motors and 5.3 LS.... I think the computer controlled or managed fuel and ignition systems give the LS a big advantage. Along with the head angle and better stock rockers. also the 6 bolt mains are a good thing and the $400 or so junk yard price. I like a lumpy idle but.... I like the LS idling at 500 rpm all day. I like the way a stock LS will shift at near 6 grand The computer tho is expensive and not simple to install and some of the gauges have to be changed and fuel system etc. In my Little C10 truck tho I do get well over 20 mpg.... so toss up for cost but I do know the LS will run 250k miles

[@gearyheidinewaccount3237]

How did you get 20+ mpg with your truck ? My '03 5.3 half ton gets 13....15 is the most I've ever seen from it... And of course that's with an overdrive transmission. I did get 20+ from my 68 327 with no over drive in a 69 elcamino and a 69 Chevelle.

[@doranmaxwell1755]

@@gearyheidinewaccount3237 Well for one the truck weighs 3200 lbs. I had an el camino also with a 454 and 6 speed and if I was really careful I could get close to 20 on the freeway. Hell... I don't know what is wrong or was wrong with you pickup but my 05 Tahoe NEVER got less than 16 and I got 21 on a trip both there and back 700 miles and it weighs 4800 lbs. My C10 is running right at 1800 rpm at just under 70 mph My sons 22 half ton weighs 600 lbs more than my C10

[@nathanieljames8974]

I believe intake manifolds have some impact but I think it comes down to primarily fuel injection over carby

[@boharris8179]

Valve angle is the old SBCs limiting factor. I've seen how big a difference a 18d head makes on the old mouse

[@lucasamick7940]

Richard, I’ve always enjoyed watching your videos. I think you are a very knowledgeable person when it comes to every day performance in every day engines. However, I cannot call this a level field of play. To me, to make it more fair, the heads should be from the same manufacture and of the same “application” i reckon you could say. Same thing with the intake manifold and induction. If it would be carb or efi. Again, thank you for all the info you’ve given over the years. No day is a wasted day if you’ve learned something new.

[@tigererickson8375]

I think it's a combination of all that you said, combined with fuel injection. Especially in combination with the angle and runners/tb

[@3foxstangs]

So many great reasons mentioned. Valve angle, efi, manifold profile, etc etc. I full heartedly agree with them. I just wanted to add one more idea. The intake manifold on the ls doesn't have hot coolant running through it if I am not mistaken. The composite manifold is also more of a heat barrier, not a heat conductor like aluminum. I am by no means saying this is where all the power is coming from, but I do believe it helps.

[@K_M_M_G]

Great video! Lots of variables to consider here. I'd say it comes to heads/cam and small amounts with EFI. Both are great motors but like technology everything advances with time

[@Stewysleepers]

You can correct me if I'm wrong but I believe that LS has a different firing order. That in combination with a larger diameter camshaft that gives you a smoother lift is where you get your extra power.

[@1452-w3b]

Not going to lie I’m kind of surprised how close the small block got to the LS. For sure though the LS had a lot better valve angle in my opinion and even though the heads flowed the same amount the small block Chevy did it with a smaller cam so I would think giving the small block Chevy a little more RPMs and more valve lift excluding the valve angle would probably put it near the LS

[@FatalReactionPB]

Possibly a medley of reasons... I'm guessing a lot of it has to do with valve angle, also wondering if ignition systems might have something to do with it... C.N.P. vs dizzy... Just a thought. Something to try might be a single plane with a carb/sniper type setup and coil conversion.

[@ktm450sxpro111]

The Sbc are definitely good motors. But in a forced induction application the ls will always trump it with better heads and a more secured crank do to the 6 bolt main design.

[@Bman_1974]

Theres still a lot of people running a small block chevy beating the ls platform

[@Crysmatic]

the same displacement, same valve size and flow. you could/should have put the same cam specs in both. they both make similar peak power which shows they both move about the same amount of air. The longer LS runners definitely beef up the mid-range; the single plane, carb, and big cam didn't help. how did timing curves compare? the LS has a bunch of small improvements that help. When GM changed to a 4" bore on their 383 crate engine they noted it had slightly better low end torque. of course piston speed affects where you make torque.

[@jayallen408]

Run them both with a Holly LS intake sounds like everything else is close enough to the same spec’s

[@dr_tate]

Speedmaster on the Small block when your going up against an LS. Doesn't seem fair. He should run them both with same manifold and carb. Maybe both with Holley Hi-Ram Dual Quad

[@DrewLSsix]

How are you going to run an LS intake on the SBC?

[@albertgaspar627]

The LS is a deep skirt block--its more a Y8 than a V8. So if you run more stroke, the piston goes further down the bore at BDC. this will compress whatever air, fuel and oil mist, is trapped inside the crankcase. The bigger the crankcase space, the less compression of this atmosphere for the other pistons to fight against traveling down the cylinder during non power strokes. But the big advantage of the Ls is its valve angle in the head--big ports tend to just shift power bands to a higher RPM (like say a Boss 302). There may have also been a difference in runner length in the intake manifolds.

[@scottleggejr]

One big point in this is ignition, which wasn't really covered (maybe I missed it?) but total timing at tq peak and hp peak would be cool to see too. Also the firing order/harmonics has some net impact I would imagine as well. Did you 4/7 swap the SBC or was it 18436572? The LS is 18726543 stock and I've only heard of a couple people ever mess with it on an LS. This test would be really cool to see taken to extremes. Dry sump, crank position sensor the sbc to keep the parasitic losses the same, etc.

[@RJZJR1]

Back again... I think a 408 ls 6.0 blk. 4.0 crank , 6.200 rod and matching piston ... 823 heads just might do it. Guessing right around 600 hp with the famous btr cam... Love to see it.

[@erenzoscroggins8056]

455 Buick Buick Buick Buick🗣😁💪🏾💪🏻💪🏾💪🏻💪🏾

[@Jfrgarage]

A Buick Olds Pontiac 455 shootout would be sweet

[@hayden6056]

@@Jfrgarage took the words right out of my mouth. *Insert meatloaf here"

[@SpecialAgentJamesAki]

Bump for BOP shootout!

[@marcalampi5036]

​​@@JfrgarageOlds won!

[@thomasgulliver3208]

Also the ls has a larger cam core allowing for more aggressive profile on the cam. Valves spending more time at a higher lift even though they have the same specs.

[@krisjones1286]

Great comparison! Keep it coming. No doubt the ls is designed better (gm engineers obviously learned something in 45 years 🤣) and the valve angle definitely has something to it. Remember the 18 degree sbc heads? However to omit that infinite ability to time vs a spark that hits every 45 degrees of rotation irregardless of the cyl need? In engine masters they killed close to 100 hp by getting the timing wrong and could only kill 30 hp by running pig rich. Timing is way important and not just the intensity of spark but when it also happens is critical IMHO. Many limitations to a distributor and different length plug wires moving parts wear over time. I would rod either one with a smile a ticket couldn't wipe off my face!

[@johncunningham4827]

Liked the comparison, I would suggest intake closing could have an effect on power considering with the difference in stroke between engines as well as the added valve lift of the LS. No cam specs provided. jc

[@vikenlink]

I’m sure the LS Stroker will produce more power above 5000 rpm with a comparable carburetor and intake manifold. To bad the test wasn’t done with a same spec camshaft on the small block Chevy 383 with the LS stroker camshaft specs . I’m convinced the small block Chevy 383 has a disadvantage with having to big of a cam and smaller stroke .

[@andrewlanger2168]

I believe there are a few things at play here, stroke, intake, fuel system, and ignition. The LS has a larger stroke so we all know that's good to give you more torque and the modern intakes, fuel injection, and direct ignition are going to have a serious advantage over a carb, distributor, and older style intakes. I would say run the test again with something like an Edelbrock pro Flo 4 and MSD direct ignition, though you may need to run it on a mega squirt 3 so they can communicate with one another. I believe that will make up most of the difference but it's going to be hard for the small block to compensate for the larger stroke of the LS.

[@michaelstoker6710]

A set of 13 degree sbc heads would really change the out come.

[@b.c4066]

That and a raised cam tunnel block. With a 55mm cam core I agree it's not a fair comparison. Build both to comparable bore stroke cam design benefits and a good sheet metal mpfi for the sbc power difference would be drastically reduced.

[@gnarkiller]

@@b.c4066 but now you're spending more money to keep up with LS that came out of the junk yard. LS is just a better stock platform to build from.

[@michaelstoker6710]

@@gnarkiller the ls is a great platform the new lt looks to be a even better platform. With that being said the old gen 1&2 sbc are really good as well and can make good power

[@b.c4066]

@@gnarkiller absolutely, but to compare them in their current states of tune is akin to comparing a 265 Windsor to a 408 dart block Windsor with high ports. Not subtle differences, huge difference in just about every aspect of each engine bro. That's all I was thinking when I posted my thoughts.

[@causeimbatmaaan]

@@b.c4066 not disagreeing, just adding: the "ls" is a sbc with most of the improvements people have made over the decades built in. Without the small block there would never have been ls. Love how the arrogant engineers said they designed a brand new engine from scratch.

[@ryanmoore7127]

i have an analysis. i am a gen 1 small block guy for starters. the 23 degree valve angle hurts flow. when you gave us the head flow that was peak flow. 13 degree valve angle deffinately improves low lift flow which in my opinion is more important. also fuel injection especially fast xfi will undoubtedly be far more accurate and efficient than a single plane and holley combo for mixing fuel. i believe ls engines have a deffinitive cylinder head advantage, but i always found them to be less durable than a gen 1 small block. seems like every week i hear of someone blowing up an ls and also hear of stories of gen 1 small blocks running for 30 years 500,000 on the odometer without any major maintenance. thats my analysis