347 STROKER vs JUNKYARD 351W-SBF DYNO DUEL!

347 VS 351-WHO WINS? BORE v STROKE, SHORT v TALL DECK-FULL DYNO RESULTS. WOULD YOU RATHER HAVE A MODIFIED 347 (302-BASED0 STROKER OR A MODIFIED 351 WINDSOR? CHECK OUT THIS COMPARISON BETWEEN A HCI 347 AND AN HCI (JUNKYARD) 351W. WHICH BUILD IS BETS, OR, WITH SIMILAR DISPLACEMENT, IS THERE EVEN A DIFFERENCE?

[@jamesreeder5316]

Back in the 70's I was a chevy guy then a mopar guy and it always amazed me at how often these ford 302's used to come along and give us such grief by being beaten by them time and time again to the point that I eventually became a ford guy too and still am after all these years. I still like chevies and mopars as well and there's nothing like American iron and just the sound of these engines reving up still excites me no matter which brands they are.

[@johnsheetz6639]

Always just loved the way the old 5.0 sounds. The new one sound beautiful as well but it's different with the four valve I guess kind of like picking between a Stratocaster and a Les Paul guitar both sound good in their own way.

[@vtecbanger3180]

I’m a ford guy now too. Started with f-body’s then went fe390 ford then went corvette and now I own Honda and foxbody. They are fun as hell. A corvette is awesome too but 2 seats sucks. Never got into mopar because the hot rods cost a lot up front.

[@dennisrobinson8008]

How did you feel about 4v Cleveland?

[@vtecbanger3180]

@@dennisrobinson8008 don’t know anything about it

[@dennisrobinson8008]

@@vtecbanger3180 Basically in 1969 the Cleveland head was flowing 275cfm@.600" using canted valves which open towards the center of the bore. The valve sizes were 2.19" and 1.71". With a valve job they do 290cfm@.500" and 310@.600" and with porting and a valve job they do 310cfm@.500" and 335@.600". With extensive chamber and port rework they were able to get the heads to over 350cfm ( Glidden -- look him up ). Basically the head have similar potential to TFSR ported and a little below the Yates. The heads were banned from racing: In this link Drag boss garage discuss all the benefits of the Cleveland architecture. kzbin.info/www/bejne/lWXPYXmbasahnpY

[@iliketacos2763]

Stunning results with the 351 Edelbrock package

[@SophiaAphrodite]

It comes out to $11 per HP which is amazing value.

[@modmotorheadful]

Love when you do sbf testing

[@jeffschwartz5199]

You don't do things wrong , man . You test . I like tests , especially when someone else is doing it 🙃

[@GJ-DT]

1 thing not mentioned is the 347 is a fresh motor with 30 over pistons, 351 is junkyard standard bore low compression with who knows how many miles.

[@deansapp4635]

Good point

[@GJ-DT]

@@janofb 30 over means alot when pistons are flattops and other motor has soap dish pistons. Fresh bore gonna seal things up a bit better also

[@paulwhite9020]

Yeah, I'm tellin ya that compression is the big factor here. Drop some flat top pistons with new rings into fresh cylinders and that 351w would stomp that 347. It's a fantastic comparison, but let's be real here.

[@GJ-DT]

@@paulwhite9020 💪

[@erikturner5073]

Plus the 351 has dished pistons. That has a considerable hinderance in power(lower compression)! Put flat tops in the 351 and send those 347 guys pouting.

[@dumpl3dore]

Unless one is constrained by space limitations a 351 is the better choice for an all around performance choice. More torque and horsepower in the everyday useable range all the way up to 6000 RPMs in this example PLUS, big plus, the 351 is much less stressed than the 347 and will be far more durable over the long run.

[@markmccarty9793]

We were turning 6800 with a stock block. Had an aftermarket rotating assembly, but stock stroke, rod length! Flat top pistons ,aftermarket but stock wrist pin location! Car ran 6.51, once and never over 6.60 1/8 mile, never on gas!! All motor! Build what you want, but a Windsor block will hang in there!!! The heavy crankshaft with those 3" mains scare people, but they hang in there for cheap!!

[@bradgriffith4231]

ZERO difference between the 347 & 351 IF the same parts are used in both. The 347 might even make slightly more HP because of it's 0.030" bigger bore & 0.010" shorter stroke & 100lbs lighter in a car! The difference in this test was new high performance parts in the 347 & a "junkyard" 351.

[@markmccarty9793]

@@bradgriffith4231 ! The block and crank is the primary difference!! Then there is the rod stroke ratio!! We've ran both!! The rod/ stroke ratio alone is the deciding point!! The only argument is the 3" main bearings, and I can tell you a 351 can run 6900rpm all day long!! Noone believes that it's a 306!! The Windsor is a stronger platform! I recondise your constitutional right to be an idiot!! The 347 is a hand grenade!.A cheap 357 will hold up night after night shooting 125 on it! Ran both! The Windsor will hang in there!! No problem! And you don't have to scream them!

[@bradgriffith4231]

@@markmccarty9793 EVERY real motor builder says rod/stroke ratio is totally irrelevent & Engine Masters proved it when they took their mule & swapped only the rods & pistons. Our ALL MOTOR door slammer has gone 7.96/168 in Phoenix in JUNE with 4,000 ft altitude air density, on race gas with 1 Pro Systems carb. NO HUFFER, NO JUICE, & NO HAIR DRYERS!!! How quick & fast is your slug? You have the "right to be an idiot" MORON! I have a pic of the time slip but can't post pics here anymore! There is virtually ZERO difference between a 347 & a 351 other than deck height & weight when built with the same cam, heads & comp ratio!

[@Stroke2Handed]

True, but not everyone wants to build a 351. I've built a bunch of different Ford engines, 5.0 is more cost efficient. My friends all told me I was crazy for building a Ford 400M, but I had never done one of them, yet I had built probably twelve 351W by that time. I like to be the winning underdog.

[@johnheindel5232]

I love your graphical presentations of the results. That is the ONLY way to see any differences. Thanks.

[@WaspMedia3D]

I'd take the 351 hands down ... more peak torque, and more HP and torque across 80% of the usable power RPM band. "HP sells cars, torque wins races" - Carol Shelby

[@joejones9944]

Sounds Good 2 Me

[@mjcmustang]

True, but you'll get a weight penalty with the 351. If you're taking turns and need to stop quickly, less weight the better

[@ericrobison8591]

The 351W is God's engine. It's what Jesus runs in his fox body.

[@johngregory4801]

@@mjcmustang Aluminum block

[@mjcmustang]

@@johngregory4801 can get an aluminum 302 as well 🤷‍♂️

[@johnbehneman1546]

GREAT VIDEO RICHARD!!!! SOMETHING I AM CONSIDERING FOR THE FUTURE!!!! THANKS FOR SHARING!!!! I LEARNED SO MUCH!!!!

[@russellhalford8811]

Thanks for the vid! I like both engines. The Windsors are beasts. As always, it depends on your specific demands placed upon your specific engine build. My old 1981 Bronco is going to have different demands placed upon the same powerplant as a 1984 Mustang GT 5.0.

[@bluecollarfox916]

Very well explained. I’m a strong believer that a motors potential to make power is solely based on its displacement. All other things being equal, the higher motor will win. If you put the right heads/cam in a 351 it’ll rev out to 6500 too. And make more power than the 347. Keep it up. You know your stuff

[@timweb1510]

More sbf

[@garyshanks6269]

Great video. Final thoughts are right on target (in my opinion). Keep em coming Richard.

[@johnbrooks2122]

I thought the same thing about the stroke. Dam bro u are the man wish I had ur guided info years ago.lot of respect!

[@stevemunro4858]

Super informative tests, and videos!

[@bobkonradi1027]

Wouldn't we all like to see a comparison test where both engines had the same spec cam, and the same heads. Plus the same compression ratios. That way we could judge the configuration differences on an apples to apples basis.

[@randallmason9687]

351 with Edelbrock top end package, bang for the buck!!

[@SophiaAphrodite]

$11 per HP is a great value.

[@markmccarty727]

Like the videos. The 351 combo here looks nearly perfect for my 94 f150 build. Lot of other factors near tho, rod stroke ratios!! Think that's a big factor in the curve too. That 9.5 deck height and 5.969 rod makes for a good street motor. After years of watching 347's self distruct I'd never have one tho. Wrist pin in the oil ring land! 7500rpm passes, weak stock blocks, po boys need to build one motor that will stay together. Been awhile but I think 347 rods are 5.4" at best! Just think about a good set of heads on a Dodge 360 with those 6.2" rods! Run forever if you don't spray it to death!

[@floydmarseeii4007]

Love the 351w’s especially in my Foxbody. The junkyard 351 with the Heads and cam swap with the 750 carb is very impressive gains!!! I don’t have the head and cam swap but I run a RPM intake with a 750 carb. The torque difference between it and the 5.0 is crazy.

[@martinellul1604]

One thing I noticed when going from a 351w to a 302w was a very obvious improvement in handling and steering response with the 302w

[@bjsteg79]

100 lbs in the nose makes a huge difference

[@radioguy1620]

@@bjsteg79 Ran my 66 Stang around my usual corners one day without a hood and could notice a difference, Hood weighed 75 lbs, put on a glass hood with no hinges and battery in the trunk for some more help too pretty easy .

[@williamlarimer334]

If my old memory serves, a 351 weighs about 60 lbs more than the 302. the one in this test would weigh less than a stock 221 (about 450) with iron heads and manifold.

[@Airpig]

With aluminum intake and heads the difference isn't at all noticeable.

[@MrMelvinkennedy1]

This guy has the best channel on youtube hands down

[@philliptropeano8399]

Good explanation between the 2 engines

[@njseashorechas2698]

Love the SBF, Thanks!

[@theozman38]

Those are the cream of the crop from Ford. 4ci and stroke variants change it identifiably so. WOW 🤩

[@madmod]

Yepsir. In conclusion, they both rock.

[@maximusvonce1381]

Stroked Windsor will destroy a built 347. I know cause i have one.

[@madmod]

@@maximusvonce1381 You can have all the cubes in the world and it wont help you if you cant feed it. It comes down to where you want to make your power and how mild the combo has to be when doing so. Realistically, they offer heads, cam, and induction that can easily support 600 naturally aspirated horsepowers with off-shelf parts whether your at 347 or 408+ cubes. I just don't see 5.7 liters of engine being the limiting factor when talking about small block fords. Look how fast people go on 300 cubes.

[@maximusvonce1381]

@@madmod Comes down to physics. A bigger motor just as heavily modified will always trumped a smaller one. I spin mine to 7200rpm like a swiss watch.

[@madmod]

@@maximusvonce1381 "Physics" lol. When your limited in available headflow, cam timing, and induction on a given application, in this case a sbf, the same level of induction needed to feed "XXX" horsepower on a 351w stroker would likely support exactly the same power on a less cubes however it would take more rpms out of the smaller combo. Hence my saying, "it depends on where you want to make the power and how mild it should be when doing so". I dont care how much power your 4XX~ cube stroker makes. Theres guys with 300 cube small blocks averaging more horsepower and torque than you and they shift far past 7200rpms. Its a bit nonsensical to claim bigger is end all be all specifically when talking small block fords lol.

[@madmod]

@@maximusvonce1381 I can list and link a handful of 310ci class cars that trap low 10s, high 9s na and shift at 9200rpms. Stock untouched 302 bottom ends have been mid-high tens na for well over a decade. Not trying to take anything from the go big displacement crowd but that isnt at all needed for most peoples power goals. I think it mostly comes down to people trying to make comparable power in a more mild combo. Neither is better than the other.

[@johnbehneman1546]

GREAT VIDEO RICHARD!!!! I AM CONSIDERING BOTH OPTIONS FOR MY EDSEL. MY MAIN CONCERN IS PARTS AVAILABILTY RIGHT NOW. AND I WANT TO ADD A SUPERCHARGER AS WELL. WITH A MANUAL TRANSMISSION. GREAT VIDEO AND THANKS FOR SHARING!!! I LEARNED SO MUCH.

[@jeffschwartz5199]

Oh heck . I watched again , lol 😆 now I'm confused 😕. Guess I gotta watch it again .

[@markmccarty9793]

The difference in the weight of the crank, rods, and pistons comes into play, plus adding some more camshaft timing and lift would be easy in the 352! When you've split that 302 block that heavy 351 will still be thumping! Wouldn't waste my time! Been there, done that!!

[@giles-df9yu]

Correct without the timeing this is "look at this different shade of apples "

[@markmccarty9793]

@@giles-df9yu yep, the only downfall is that heavy crankshaft and its wider. Build a 393? I like budget factor, and the durability of the stock crank/rods!

[@FootageFactory]

Precisely the topic I want to explore!!

[@elmerfudpucker3204]

Milder 351 stock stroke and rotating assembly basically has the same power as a high dollar, fitment required unit. The moral of the story is, "There is no replacement for displacement.".

[@DarkLinkAD]

"Except for boost"

[@midnight347]

@@DarkLinkAD but when you have more qubes with the boost all things equal the larger displacement makes more power. So really boost isnt really a replacement. If everything is equal larger displacement makes more power. Yea smaller displacement with boost can outdo larger displacement but if they both have equal boost larger displacement always comes out on top.

[@DarkLinkAD]

@@midnight347 Its a lot easier make 15psi boost, than to afford a 700cu in 11.4L engine. Far less drag too.

[@elmerfudpucker3204]

@@DarkLinkAD Yeah, then you "boost" the larger engine, and there goes your exception.

[@TwoLotus2]

No replacement for cubic $$ MONEY $$!

[@jplperformance9073]

Love the tests

[@TurboRanger351]

351 all day. Because the block is stronger. And you can still pick up another 100 cubic inches.

[@richardholdener1727]

GOOD POINT

[@BC08]

I agree

[@carlspackler9550]

Looking to build a 347 for a Sleeper project. This channel is great.

[@davidtucker3729]

and these same rules apply across the big three and their respective engines of yesterday. Nice comparison

[@jimerjimer9250]

These vids are giving me the itch to pull my 89 notch out of storage.

[@genemounce8302]

PERFECT timing R.H. ! ! I just sold my LQ4 block/gen4 rods/pistons/317s to build a 347 out of a vintage '68 302 casting block for my '68 coupe ! !

[@ivancolesnic]

Don’t do it man!!! Do a 351 stroker. I drove around with a 302 based 331 with afr 185 heads for a year and it just wasn’t fast enough. A 383 or a 393 is just so much more everything. I ended up with a 388 and I love it.

[@genemounce8302]

@@ivancolesnic I'm just look'n for some motivation for an old crappy car on the 'cheap'. I'd def do a 351w based engine if i had one lay'n around.

[@ivancolesnic]

@@genemounce8302 consider that a running 351w is cheaper to buy than a 347 rotating assembly. If you are looking for a budget build then stick to a 302 with gt40 heads.

[@genemounce8302]

@@ivancolesnic ...and a cam, can't forget the cam. LOL

[@ivancolesnic]

@@genemounce8302 only the wrong cam though

[@magdump7380]

Love me some Windsor.

[@sknallt2010]

As always, great vid! I would like to see two things in future videos: 1. How much impact has the ignition system (points, Pertronix (I-III), Duraspark ect). Doe it have an impact and if yes under what conditions. 2. Comparison of exhaust manifolds of a 289 (stock, HiPo, shorty and long headers). This would be awesome!

[@sknallt2010]

@@429thunderjet2 but what does better mean? Is it measurable? This is why love these videos so much. Richard shows facts straight from the dyno. No guess work, facts!

[@sknallt2010]

@@429thunderjet2 do you hear us @richardholdener

[@alexisacevedo8016]

Change only the 112 to 108 lsa and the 351 will pass the 347,take the challenge,only this change👍

[@smurra3]

Back in 1984 a friend and i were driving thru kansas City, one fine spring day. I had a 1971 ford Maverick Grabber 302 with a 3 speed manual transmission. We drove by a 1969 Mach One Mustang that was For Sale, in front of a Auto Parts store. We turned around and went inside. The older guy said it was his sons car he was selling. He took us to the back to some stairs and said "My son live upstairs go wake him up" So, we go upstairs the guy is a senior in high school just like us. I told him i was interested in the car and could we check it out.. He said ok if you will smoke a Doobie with me first. We were like "Far Out Man". So, we were talking and i asked him about the car. He said it used to be his dads, and it had a 351 Windsor with a 4 speed manual trans. He said his dad who owned the shop was a U.S. Army Vietnam vet. He said he bought it after he got back when it was two years old. He said he rebuilt the engine and modified it. He took us outside popped the hood said it had a 750 carb, It had Aluminum intake head work 10.5.1 pistons. I noticed on the front it had a vanity tag that said "Chevy Eater" He said his dad used to race it. He said he would drive it first t hen let me drive it. He fired it up and it sounded incredible. He got out on the highway and burned the tires thru third gear let up a little it grad and to off like and Arrow. We were completely Amazed by the Brute power this thing had. He then let me drive it and i could not believe how much raw power it had. I had driven my friends 1971 Dodge Challenger 440 4 speed with dual 4's and this 351 Windsor would have waxed it. I got the guys number and drove back to Topeka, went to the bank to get the loan. I called the guy later that afternoon. He said that he sold it to the next guy that had drove it. That car had to have well over 500 Horsepower....

[@dh1240]

Never mentioned but these 2 have very different rod/stroke ratios. Great information in these videos as real world tested power shows that displacement + airflow = power. Really puts into perspective where money & effort is best spent.

[@bradgriffith4231]

Rod / Stroke "ratio" has zero to do with total HP produced. Engine Masters has already shown that, as well as showing fuel octane rating makes almost zero difference. Their mule made witin a couple HP on all pulls regardless of octane & required exactly the same 29* ignition timing from 87 all the way to 115 octane race gas.

[@The-carpenter-420]

People talking about a new fresh motor against a junkyard wore out motor being a disadvantage but people forget loose is fast. Thats why they always run best right before it blows

[@vincentrohmann5599]

Very informative

[@michaelgiglio1571]

Good work Richard. Just as i expected between the two engines. And everything you said is true. Mick from australia

[@DBSSTEELER]

I'd like to see the same test run with both blocks running the same set up with the same compression. The power would be nearly identical but it would be interesting to see exactly how much difference and the shape of the curve.

[@sorshiaemms5959]

MAKE THE 351 030 OVER

[@bradgriffith4231]

The difference would be miniscule.

[@AU10ZC]

If it was same bore and stroke between the two the tall deck would make more power, and it's not because of a better rod to stroke ratio. It would be because any turns in the intake manifolds runners are not as tight, therefore more free flowing compared to the short deck. Case in point is any of the 2 piece EFI intakes. Particularly cylinder 5 on the GT40 family of lower intakes.

[@lloydholt6511]

Interesting tests.

[@jjs777fzr]

Back in ‘93 I owned a 90 Mustang LX 5.0L that I wanted a Crawford 347 stroker so badly. But it was cost prohibitive. I was just 22. Ended up spending money on my short block at Nat’s Racing Engines in Seakonk, Ma. Threw on aluminum Edelbrock heads, low compression Paxton VR4 and a little 125HP shot of juice in 3rd gear went 11.7 @124MPH. That was driven easy no powershifting I only had a T5. Always wanted to see what a 347 would have done.

[@PeeterPuncher]

The compression ratio is probably the factor.....replace those stock pistons in the 351 with some flat tops and it would be a monster.

[@davidtharp7767]

I would really Like to see what the 351 would do with a fresh set of flat top pistons & 30 over for a Fresh bore & a Rebuild to un-Do the diff between raggedy 351 from Junkyard & fresh brand new 30 over 347. My Bro put the Edlebrock top end ( heads & intake, etc ) on an already strong 350 Chevy in a 40 Ford Koop & I could not believe the Diffeerence it made. I believe the Cam is Part of the Head & Intake Kit. That 350 Chevy Sounds Righteous for Sure while it is Pushing You Hard back into the Custom Upholstery on each Shift. PLEASE DO Freshen Up the 351 with Flat Top Pistons & Let us See the Dyno Chart of the Fresh Better Compression 351 Windsor !!

[@bradgriffith4231]

Compression is not a major factor in HP. Hot Rod mag did a test years ago using a 440 Dodge motor because there is no "quench" area in the stock heads. They stacked head gaskets to alter the C/R 1 point at a time & the change made minimal difference & a lot of the difference can be made up by cam duration & valve timing. Low compression needs a little cam to increasse cranking pressure & big compression needs much more cam to relieve cranking pressure.

[@randyduncan795]

Great vid! So the big Windsor is bulkier and heavier but it'll crank that power out for a quarter million miles whereas a 347 is lucky to do 50K. Easy choice if it's going in a truck.

[@ProjectFairmont]

The short deck SBF with its smaller diameter main journals for this engine size comparison is superior in terms of RPM potential and being lighter and physically smaller is idealized for smaller cars. A 351 based stroker crank makes more sense for the overbuilt Windsor, and more idealized for larger cars and trucks.

[@andrefecteau]

yeah, I have one, it's a beast a 427" in a 95 Mustang

[@dennisrobinson8008]

Theoretically. Holdener says dyno results don't show a noticeable difference between bearing sizes.

[@stevecooper8121]

I would have guessed the 347 with higher rpm would have had 50 more hp than the 351w.That old junkyard dog has some bite. Love my 351w in my old heavy f150.Shes a old sleeper with a whole lot of bite.

[@donreinke5863]

Enjoy doing things the easy way with off-the -shelf parts while you can. If the environazis at the slimy EPA have their way you will be casting up your own heads and manifolds in a pit dug in your backyard (the way it all started with performance castings) and machining your own camshafts/stroker cranks from a chunk of steel.

[@peterdragon9630]

Big block type power without the weight, actually surprised. With the aluminum heads, intake, use of aluminum water pump and headers I wouldn't be concerned about the weight factor for my truck and the 351W is a stouter block. Will work for my application and save a lot of $$$.

[@vxer1000]

The big difference between the 351W and 347 stroker. 351W has a taller deck height. This allows a longer connecting rod which improves the rod to stroke ratio increasing torque throughout the rev range. The 347 has a lighter crankshaft due to the smaller main journals which reduces rotating mass. This, in combination with the shorter deck height and shorter connecting rods, creates less rotating mass which allows a quicker spin-up translating to more HP. The 351W is a better base to start with if high HP is the goal. Given the right cam, head, connecting rod, compression combination they can go over 800HP.

[@richardholdener1727]

disagree on the effect of rod ratio

[@bradmaas6875]

After fitment comes cost. Finding a running 347 in the yard is highly unlikely.

[@larrylaverne9547]

Nah, just have an old 302 block bored and stroked, then throw some inexpensive AFR 185 heads on it. This was my build on a damaged 302 and it cost: $900 for the complete forged piston stroker kit, around $800 for the block work and assembly, $300 for the cam, $1,500 for the heads, and I had good 'ole TMoss port the lower intake for around $300.

[@bradmaas6875]

@@larrylaverne9547 $3,800 vs. $800 for a runner 351. Cost effective.

[@larrylaverne9547]

@@bradmaas6875 That's $3,800 for a brand-new 347 VS an old 351 that lasts for 100K if you're beating on it. So, no comparison. Try to build a 347 equivelant for $3,800.

[@bradmaas6875]

@@larrylaverne9547 add a bit more if you don't have an engine to start with. You have two engines, a 302 and a 351. Build them stock or pump them up, the cost will be very similar but the power will not. The 351 will have more HP and torque.

[@larrylaverne9547]

@@bradmaas6875 A 351 block costs more, if you can even find one. Parts cost more, parts are less available, fitment can be a serious problem during and after installation (just TRY to do a simple plug change!) It weighs more... noticably more. I had a Mustang with a 351C, and later, one with a 302 (5.0L) That 351 handled like a fat pig. The understeer was just rediculous. The 302? Felt like a feather, a joy to drive in the mountains. You blow-up a 302/347 block? NP, get another one for $150 or less and do it again.

[@keepondreaming3870]

Well, you compaired a junk yard bottom end to a build 347ci. One thing you didn't mention, is a 351w stock block, will hold 800hp conservatively, more if built right. 347ci , 302 base will only hold 500-600 ish , one over rev or one too many hard launches on sticky tires and block split/ cracks right down valley. This I've learned this from experience, building theses. In addition, the 347ci made more power up top because of cam duration and higher lift. I would of loved to see both side by side .030 builds 351vs 302, Same cam, same Heads. On Dyno. Cheers, Keep on Dreaming 👌

[@AntiPattern328]

You have to understand the 347 is a "Stroker". You've already spend $2500 - $3000 on that engines rotating assembly and block work before you do anything upgrade wise. $500 or whatever for the 351W from the Junkyard.

[@killfoot961]

Knowledge is power.

[@ytmachx]

In my experience LSA makes a big difference and the compression

[@rickmurphy2959]

I'd be interested in seeing the results of a leak down test on both engines.

[@DillonAuto]

Good presentation. I was going to expound on a point but he covered it. Meaning "Windsor" style Ford heads and they need that split duration in the cam because they don't breathe....compared to a as built high performance head.

[@richardholdener1727]

performance heads use split duration cams too

[@DillonAuto]

@@richardholdener1727 It depends on the set up, (nitrous)and the Windsor head struggled with exhaust flow, compared to others. Subscribed.

[@SPURTIS00]

Good informative video. I'm doing an engine swap into a 1955 T-bird which doesn't have a lot of vertical space to work with, so I'm dealing with - as you mentioned - the fitment consideration. The baby birds are much shallower vertically through the body than the regular full size fords of the day. And it isn't obvious when looking at one of the old T-birds, but that hood scoop is necessary. The air cleaner on the Y-block fits right up inside the scoop with only about an inch of vertical clearance. And I want to be sure I have room for a nice tall, high flow air cleaner on my swapped engine. So after a lot of consideration I'm going with the 347 stroker and not the 351 based engine. Also, the 302 based engine is considerably lighter than the 351 (50 lbs or so), which is important to me as I want to shave as much weight off the front end of the car as possible. Thanks for the good thoughts in the vid.

[@sorshiaemms5959]

THE WINDSOR IS A MORE HEAVY DUTY BLOCK CAN TAKE MORE POWER AND MATCHES THE Y BLOCKS SIZE AND YOU DON T NEED A STOKER KIT MORE TORQUE WITH LONGER RUNNERS

[@cavscout62]

Spend the money, get an SHP Block and build a 363 for that T Bird. Power, reliability and longevity. Period.

[@DWBmotorsports]

I actually bought this xfi cam from you a few months back. I’m putting it in a low buck 393 stroker for my fairmont wagon. Eagle cast 3.850 crank, stock rods, and 302 pistons. You Xfi cam and air gap intake with Victor jr heads. Shooting to make over 500 streetable horsepower. Fingers crossed.

[@DWBmotorsports]

@Skip R the goal was to make 500 horse with things I had or could get very cheap. I ridge reamed the block myself and dingle ball honed it. I have $570 into the whole rotating assembly. I couldn’t have done a 408 for that cheap. The biggest factor in that was likely reusing the stock rods, but for some reason the 302 pistons are much cheaper than the ones I was going to use for a stock stroke Windsor.

[@northfloridacowboy8728]

You gotta cut on that block too for the crank on the 408. I like the 393 myself, I'm putting one in an 86 f150 4x4 with a 5 speed and 393 gears.

[@DWBmotorsports]

@@northfloridacowboy8728 with stock rods you have to clearance the block near the oil pump and bottom of the bores so the rod bolts clear. Easy peasy

[@jesusisalive3227]

The 351W is a heck of an engine!

[@sorshiaemms5959]

HARD TO BEAT ALL AROUND

[@nickking1510]

Got one in my 1977 searay original engine runs like new never rebuilt well maintained by original owners now the Omc outdrive work in progress lololo

[@chrishenirksen1705]

He is right if you gonna do any kind of work on the top end you're gonna get lots of torque I know I build A331 stroker But yeah having a good rotate assembly is a good foundation for the block And it also depends on how you wanna build your motor I built my motor to get from point a to point B as fast as I can

[@GimpyHSHS]

I’m glad you mentioned the cost difference at the end. The 347 is pretty much the max on a stock block, with the more expensive stroker rotating assembly already there. A comparable 408 that would cost about the same to build as a 347 would’ve likely bested the 347 everywhere. I’m going 427 right now, and people have questioned why I’m not going 363 instead since I AutoCross and track the car...64 cubic inches is why. It’s hard to make that difference up anywhere else on a NA application where I want good low end power AND some steam at the top.

[@robertaranda7371]

Depends on what your goals are. The 347 is more expensive and typically a weaker block if running a factor block. Stock block safe at 500hp while stock block 351 is good to 750hp with upgraded rods and pistons junk yard 351 is probably $500 while a 347 is about 3500 for short block. Now if you are into foxbodies you will need a different Intake, 351 specific headers and oil pan with drop motor mounts recommended. Now if your car is already stock it really doesn't matter because you will need to upgrade these supporting mods anyway. Now if you already have headers, upgrade Intake, oil pan and motor mounts I suggest just upgrading to a dart block if you are already paying for a forged rotating assembly and machine work. Plus you can leave your current engine in the car while building out your new setup and continue to enjoy your car. I believe stock block 347 cost about $3500 and capable of a safe 500hp while 363 dart block with similar rotating assembly is good to 1200hp. $2000 to more than double your hp capacity is a no Brainer to me. Plus 500hp stock block is one bad tune up away from being a cracked block paper weight.

[@russelljackson7034]

Right on

[@JohnThomas-vb9se]

Honestly there’s a lot of variables. The intake like you mentioned, also the rod ratio and dwell time, the large bearing journal size and rod journal size of the 351 and the weight of the rotating assembly. They’re always going to be close.

[@timothybayliss6680]

A slightly longer rod usually brings higher efficiency, but ran on a dyno there is little difference. This instance, where one rod is half an inch longer, the rod bearing is 3/16" bigger and the crank probably weighs 5lb more, the lighter rotating assembly is going to be worth some power when ran on the dyno at 300r/s.

[@richardholdener1727]

yes on intake and rotating weight

[@bradgriffith4231]

@@timothybayliss6680 Rod length has zero effect on HP output. Engine Masters did a test & the shorter rods actually made slightly more tq/hp with all else being identical

[@dilsher12]

Richard you need to do a mild home ported cylinder head test with whatever engine preferably LS .

[@RHDSIRII]

Can you do a comparison between a big bore(94mm) 5.0 Ford Mod motor vs a Stroked 5.0 Mod motor? Id love to see the difference in HP/TRQ Also love to see the effects of unshrouding the valves

[@cam3002]

Interesting video, thanks for making it. What is your opinion about how rod/stroke ratio affects the results, assuming everything else was the same?

[@richardholdener1727]

it showed nothing in my test

[@Turbo4Joe363]

I'd take the 351W! But, the 347 8.2" deck is a compact engine. So, I built an engine that's better than either.... a 4.125 bore, bullet proof, Dart block 363 with AFR 195cc heads.

[@gregpoole4364]

Haven't got through all your Vids yet. Curious if you have done any testing on combos for making low RPM torque for rock crawling or towing. Love to see a torque off with the 440, 454 and 460's or stroker variants that could drop into 70's and 80's pickup trucks. Love the videos.

[@jeffjohnon4223]

Find a old Edelbrock SP-2P intake 4 barrel,those things make supersonic velocity to the point of supercharging effect. Perfect for trucks turning big tires and crawling. I've seen a 400 Ford turning over 500lb/ft or torque not far off idle running that intake.

[@celica197263]

Hi I liked your comparison one thing overlooked is the parasitic loss of the combined weight of the piston assembly,conrod and crankshaft weight. Lighten the weight of the 351 assembly the same as the 347 and it would be interesting to see if the figures would be the same. Also piston speed is completely different with the 351 having more dwell at T.D.C. There is more than meets the eye. Cheers

[@markcole6475]

It would have been interesting to run the exact same top end on both engines! Just to see what changes the longer I take runners on the 351w do differently! Imo it’s really hard to compare bottom ends configurations without using the exact same top end combos. Interesting video tho.

[@bobqzzi]

Only way to settle this is to get custom cranks and pistons make in .030" incremements and test with exactly the same cam and heads from a stroke of 3" all the way to 4". Of course to really settle it, you need at least 3 different rod lengths for each bore/stroke combination. I look forward to these tests.

[@johnb7430]

He's basically done rod ratio tests. The power changes primarily with displacement.

[@bradgriffith4231]

With all else being equal the Bigger motor will always make more power & there's no reason why you'd need different rod lengths, since "compression height" can be changed with the wrist pin location in the piston. I'm running 6" rods in my 409" SBC & the wrist pin is still WELL below the oil ring!

[@kevmay21]

A point that I think is important is that two engines with the same cubic inch and one has a shorter stroke that engine has more max performance potential. If you were building a very high horsepower engine with enough cross sectional intake area to support very high rpm the shorter stroke is the one to go with since the mean piston speed will be at a much reasonable FPS speed vs the longer stroke.

[@richardholdener1727]

NOT A CONCERN IN THIS RPM RANGE-VALVETRAIN IS MUCH MORE IMPORTANT

[@bradgriffith4231]

IF you take 2 engines with the same displacement, say a 351 with 4" bore & 3.5" stroke, & the other with a 4.125" bore & a 3.25" stroke, the big bore / short stroke engine will make more TQ/HP throughout the entire RPM range. The short stroke reduces "piston speed" & the piston travel in the cylinder is where 95% of the parasitic drag is in a motor. The larger bore also unshrouds the intake valve promoting better airflow / cylinder filling, aside from the fact that one can run larger valves in the larger bore cylinder. EVERY well known engine builder uses the same basic formula. As Reher & Morrison has said, put in the largest piston the architecture will accomodate, then make the stroke whatever is needed to reach the desired displacement, & then use a connecting rod to connect the 2, as rod length has very little to do with total HP output.

[@nutandboltguy3720]

As for making a 351 fit in a Mustang, there are tubular k members that drop it down so you can use a stock hood.

[@jamesreeder5316]

As far as I can tell you did nothing wrong. The big reason a lot of builders like the little ford 289/302 is because it's light and small and you can fit it into a lot of small cars: Sunbeams ,Austin healey 3000's and of course the ever classic Ace roadster which eventually became the most awesome Cobra. I love the little engine because of it's fierce reputation for longevity and consider that it was very well designed.

[@chrishorst6993]

With the LSA of the cams. It affectively lowers the compression ratio on both engines.

[@bluecollarfox916]

Have any tests directly comparing carb size? Like what really happens when you run too small or too big a carb? Maybe the results are similar to what happens when you have “too big of runner” on a small motor. Would be interesting. Like 3-4 carbs on stockish motor and then the same 3-4 carbs on a modified version of that motor.

[@dfabeagle718]

What about we take the used 302 pistons left over from the 347 conversion (hopefully forged flat tops), stick them in the 351 with a 3.850 stroke crank with stock 351 rods, make an easy 11:1 and run right the hell away from that 347. :)

[@kennymilton7457]

The 387 combination!!

[@anthonysgarage]

I'll take the 351 just for the cost and the strength advantage. The only draw back of the 351 is less under-hood intake options if you wanna go with EFI.

[@Parents_of_Twins]

I was wondering why the 351 was producing more low end torque and the extra runner length makes sense and camshaft differences make sense.

[@austind6546]

Can you do a lima 2.3 turbo build?

[@vinknepprath4404]

Or how about direct comparison between Holley efi systems and fitech system have friend with a fitech system but I think its junk needs to b replaced with Holley carb... but would love to see what they both have potential for

[@EpicScandinavian]

The 347 had a better cam for all out power and that's about it. Swapping the cams would make these motors switch power curves with about 5 more ftlbs of peak torque at 100 fewer rpms and the same peak power but also at 100 fewer rpm for the 351. The tighter lobe separation angle and additional exhaust duration are the critical differences but the headers' primary length and diameter used for these tests could have affected the power curves almost as much.

[@markmccarty9793]

The 5.96" connecting rod in the Windsor is the best reason to go with the 351w! That, and the fact that the runners are longer equals more low end torque. Besides, the 351 has the ability to take far more power that that the 302 block! The only reason to choose the 8.2 deck block is the 9.5" won't fit!! Ran both, the 9.5 is heads and shoulders above the 8.2"!! The rod stroke ratio on thev347 is horrible!! There's a reason we call them hand granades!! The only drawback to the Windsor is the 3" mains, but it never was a problem for us!!

[@charleslum2438]

You can build a stroker 351much cheaper than a 347 with 400 crank and rods with stock compression hight 302 pistons and it will make North of 500 easy. Most 347 have a oil ring land that intersect the piston pins and is not something I like but it's a personal choice.

[@royenri01]

Geez, all the moaning and groaning about weight and rpm in here. Richard, I'm sure most of us appreciate the time you put into this video and showing us the power potential of a cheap, sealed junkyard motor!

[@royenri01]

Well nearly sealed. Minus the heads/intake.

[@dandel351]

The 347 has other "issues" the shorter piston skirt can cause oil control problems and bore wear from the piston rocking more. Plus the 351 has larger bearings that are more suited to low engine speed use. IMHO the more sensible stroker option for 302 blocks would be a 331ci . The wider block and taller deck height also adds weight to the picture so there are pro's and con's to each so it comes down to how much $$ you spend to get the result your chasing.

[@bradgriffith4231]

There is ONLY 0.100" difference in the stroke between a 347 & a 351, which is negligible. The pistons could be almost identical, but the 347 uses a relatively short rod & rod angularity is where "piston rock" could come into play but it would still be a miniscule difference. I run 6" rods in my 409" SBC & the wrist pin is still well below the oil ring & the deck height on ALL small block Chevies is the same, regardless of displacement.

[@daytradescottie7253]

Ima thinking that the engines would have made near identical power with the same compression ratios. Splitting hairs at that point.

[@rickygovan6295]

How much difference inn compression and combustion chamber sizing which comp is best same with combustion chambers ???? These videos are great thankyou

[@utahcountypicazospage5412]

What would’ve been cool is if he gets a junkyard motor and puts the stock cam and heads on a 347 stroker then we could see what the 351 made stock and 347 stroker With stock stuff

[@richardholdener1727]

I have run a stock cam and stock heads on a 347 stroker

[@larrybrinley8222]

@@richardholdener1727 that would be a great comparison to add to the data comparison of these two.

[@joejones9944]

@@richardholdener1727 What did it Run Like? Were The Stock Heads Atleast Decent? Thanks

[@erikrunas226]

Personality I would go for the 351 in this comparison as a nice street engine in a Fox Body if it would fit. It made more low end torque and in my experience, I never revved a daily driver over 6000. It could also be at home in a 70's or 80's F-250 with a 4" lift and 35's.

[@brianbooher7318]

It will fit i got a 89 with a 351 Windsor in it fit no problem i had to get a set of i believe it waz 2 inch drop motor mount to make 351 set same as 302.you van use stock motor mounts but I think hood might not shut

[@scottrobertson6949]

Having dealt with and built both 347 and 351w there is a major difference in the rotating and reciprocating masses. I.E the factory 351w piston is so much heavier compared to the 1.100" comp ht 347. All that additional weight of conrod and crankshaft takes extra energy to move. I believe if Richard(Bless his good heart) did just a bottom end swap you would see the 347 accelerates faster and makes more power. See if I'm not right. Thanks for the testing

[@albertgaspar627]

that's an interesting point, because if memory serves, the original 347 strokers used a cut down 351C crankshaft. most modern kits i'm sure are using a specially cast crank. The ability to rev up to say, 6,000 rpm faster with a lighter reciprocating assembly, works on an engine making more power at a higher RPM--a stock 351W head that would fit both short blocks (for example) was designed more for torque at a lower RPM. but that could always be changed with porting and a swap to chevy valves which were larger in diameter. it's worth testing your theory on a dyno. i still think the difference in connecting rod length will cause a piston speed difference, perhaps enough to cause a difference in filling on the intake cycle and exhausting on the exhaust cycle. if so, a different engine family may be needed--or one 351W with super light components versus stock OEM parts.

[@myeighty-nine7813]

351W IS THE WAY TO GO. 347 is the limit of the 302, 351 is a sky the limit kind of block stroker plus boost reliably. I actually just picked up a 351W last weekend

[@68nitrostang]

If spending money , it cost the same money for small stroker combo as it does larger stroker combo But the 351w block is way stronger than the 302 There is a disadvantage of main bearing size robbing power in the 351w 3.0 main

[@xlr8r3VA]

Richard, great job as always! I would like to see you compare a 408 Chevy small block vs a Ford 408 stroker vs a Mopar 408 stroker. Identical components as possible. See who wins!

[@richardholdener1727]

they all win

[@alvin7089]

@@richardholdener1727 Does the 302 sound any different when stroked to a 347 while idling, revving, or at WOT? And also which is safer and more reliable a 500hp NA 302 or a 500hp NA 347?

[@lifeonadime4703]

So I pretty much want cnc twisted wedge heads with a tight combustion chamber and a cam with decent duration and a tight lsa and an intake to match on a 351w to make some pretty darn decent HP an tq 🤔. I wonder what either would do with the block decked and fly cut Pistons 💪. People only hate on sbf because the e7 heads were such garbage. A well matched hci on even a 302 is not to shabby. Planning on building a sbf for my dad's 68 soon. Now I know what we want!