SINGLE PLANE VS DUAL PLANE, WHICH INTAKE OFFERS THE BEST AF DISTRIBUTION? FULL DYNO RESULTS!

WHICH INTAKE OFFERS THE BEST AIR/FUEL DISTRIBUTION? HOW CAN A MOTOR GET HURT WITH A PERFECT TUNE? WILL MY MOTOR BE OKAY IF THE AF METER SAYS IT IS SAFE? HOW TO TUNE AN LS! CARBURETED AIR/FUEL DISTRIBUTION. SINGLE PLANE VS DUAL PLANE, WHICH INTAKE MAKES THE MOST POWER AND TORQUE? CHECK OUT THIS VIDEO WHERE I COMPARED A SINGLE-PLANE EDELBROCK VIC JR. TO A DUAL-PLANE, EDELBROCK PERFORMER RPM INTAKE FOR POWER AND AIR/FUEL DISTRIBUTION. BOTH INTAKES WERE RUN WITH 8 OXYGEN SENSORS, 1 IN EACH OF THE PRIMARY PIPES OF THE HEADERS TO MONITOR THE AF RATIO IN EACH CYLINDER. JUST BECAUSE THE AF METER IN YOUR EXHAUST SHOWS A SAFE MIXTURE (AN AVERAGE OF THE 4 CYLINDERS), DOESN'T MEAN THE MIXTURE IS SAFE IN EACH CYLINDER.

[@mattg9958]

Love seeing the a/f ratio differences of individual cylinders vs dp/sp intakes. Great stuff, i cant wait to see blow thru setup next. Could you do duel 4 barrel carbs also? Great channel.

[@stickman-1]

That's why I have EGTs on every cylinder. Also you can tune the carb jetting in the lean holes a little bit. At least to get to the safe zone. Also you can port the intake in ways to better equalize the flow to a particular cylinder. I've been there and done that (just using spark plug readings 30 years ago.)

[@AB-80X]

There will never be a substitute for spark plug reading.

[@jmans093]

That's downright scary. I wonder if it would be better on the old small block firing order vs the LS one. LS pattern is regarded as a little better for power and smoothness, but maybe there's a reason the engineers chose the old pattern back in the day when fueling was a bit less precise. If the LS pattern is indeed a little worse in this regard, that might explain why GM monitors it so closely. A lot of people don't know this, but most, maybe all, GM LS/new LT engines monitor individual cylinder air fuel ratios, even with just one O2 sensor per bank. The sensor and ECM is sensitive enough to detect A/F variations between cylinder pulses and too much variation will set DTCs P219A (Fuel Trim Cylinder Balance Bank 1) or P219B (Fuel Trim Cylinder Balance Bank 2). With just one sensor per bank, the ECM doesn't know which cylinder is causing the variation, but it still knows if one of them is off beyond a certain threshold and will set a check engine lamp with one of these codes depending on the bank it detects the problem on. And it doesn't take much. Seen a lot of this code on seemingly perfectly running engines. I've personally never seen another engine family where the OE does this.

[@TomSmith-cv8hk]

Same problem different cylinders.

[@theshed8802]

I spend a lot of time looking at, and talking about firing sequence as opposed to firing order. In my opinion, what you are seeing is a combination of cylinder robbing during the induction stroke, and differences in cylinder scavenging during the exhaust stroke. Because of this, when I port intake manifolds, I bias the porting based on firing sequence, and if I'm making an exhaust, I never use equal length primary pipes, because I'm trying to equalise the pulse in the collector, not having 2 pulses arrive on top of each other, then a big gap. Good stuff Richard. Really looking forward to the next instalment

[@bryanmaloney6651]

At a pro stock team I woked at in the late 90's, we had to stagger the jetting by eight numbers to get the O2's evened out on the dyno. This was with symmetrical port DRCE 2 heads. The GM engineer said this was typical from what he had seen at other teams. He also said he had finished a week of testing at a pro stock truck team running 18 degree chevy heads (siamese runners); and they ended up staggering jetting seventeen (!) numbers to even out O2 readings.

[@richardholdener1727]

WE HAVE DONE BIG STAGGER ON BBC TUNNEL RAMS AS WELL-EVEN PUT A TOOTHPICK IN THE AIR BLEED

[@josephtravers777]

One of your best videos, Richard. I tune for the leanest cylinders to be on the safe side. The A/F comparison between intakes is great info. Thanks man! 👍

[@brracing7861]

Before I left for NNN 2023 I installed new Accel C-cut spark plugs in the 1997 C2500 454 Gen6 engine. Used Accels had 15k miles on them nice even Burn patterns on porcelain tips. Was impressed no Porting any by me pure bone stock.

[@baby-sharkgto4902]

I really like these type of tests 👍

[@tonybernheim8365]

Cool video..I have always used a open single plane type plastic carburator 2 inch spacer on both single/ Dual plane intake manifolds..Helps with vapor lock/ Fuel temp with a 800cfm Q-jet......

[@falfighter]

nice test. thank you

[@mattmorrison6958]

Really good stuff! Diving back into your channel and really digging the content lately

[@WACKOJACKO6648]

Obviously, stacks!

[@ricksshop]

Thank you for covering this. I assume the pulls were WOT, imagine the fuel distribution at part throttle with angled throttle blades in the airstream. This is the reason I usually advise people to skip right over throttle body injection and go straight to port injection.

[@richardholdener1727]

port injection is still a distribution problem with these intakes, unless you do individual cylinder trim

[@Prestiged_peck]

​@@richardholdener1727I wonder how much better it would be with a dedicated port injection intake with flow matched injectors

[@richardholdener1727]

port efi with individual cylinder tuning will make it spot on at every rpm

[@ricksshop]

@@richardholdener1727 Seems like every time I pull a carb intake off an engine and install a factory EFI manifold, most fuel distribution problems go away. Haven't added fuel rails and a TB to an aftermarket intake, which I assume is what you are talking about...

[@ericschumacher5189]

The blow through that could make in better or worse based on design. The shape of blow through hats vary pretty significantly between different manufacturers, and it would be hard to know what a “good” shape would be to improve the issue without testing multiple.

[@RobsNeighbor]

Hello Everyone!

[@Jim_Lawrence]

Ello Guvna

[@russelljackson7034]

Right on

[@TK-eg7eg]

Boost will help distribution.

[@wydopnthrtl]

1 & 7 are the front and rear on drivers side. Just goes to show that modern day FI w/an injector at each cylinder is more efficient and IMO wiser to use.

[@michaelmaher4328]

I love your information, thank you. How do you keep your engine [your body] running healthy? diet and exercise?

[@brracing7861]

Be interesting to test on a 454 Gen 4, Gen 5 454 and Gen6 454. Big Block Chevy has 2 good intake ports and 2 bad intake ports per cylinder head in Racing Porting world. Mine runs hard and butter smooth at idle.

[@dannytravis7118]

Makes me curious about a tunnel ram intake.

[@russtynuts]

wish edelbrock would offer the dual plane in a fuel injected version .. torque with the old school look without using the truck intake

[@skippy2987]

It's also worth noting that it might not be just an intake problem. Or at least I've seen evidence that the cylinder to cylinder torque production varies by a LOT driven by the exhaust design. Mostly because of blowdown interference.

[@Cammy_The_Camaro]

LOVE IT! I remember asking this question! Thank you! You are THE man! One more question, what about an throttle body efi unit? Do you think it would aid in distribution?

[@richardholdener1727]

doubtful-this is primarily an intake issue

[@AndyB718]

Ls7 motor i had done saw a 22hp and almost the same tq increase going from a edelbrock super vic to a CID. BR7 liked the CID

[@Damothedevo]

I noticed that it was 7 and 1 both times, was wondering if that was a result of firering order and whether stagered jetting could alleviate some of the leanness without richenung the entire enigine too much. Great vid, very interesting.

[@brracing7861]

I think the issue can ony be solved by cylinder head and intake Porting Richard Holdener. Not so much after hige CSA for 100+ Hp gains but to even out Cylinder Airflow and wetflow. Complex topic Indeed.

[@dennisrobinson8008]

tunnel ram for the win.

[@darylmorse]

Richard, this is really interesting. I really appreciate your insightful video, yet again. This kind of begs the question, why would anyone use a carburetor when you can fix this problem using FI?

[@richardholdener1727]

the intake design is also the problem, a trait shared with efi intakes

[@brandonrohrer7914]

Now do it with a hi ram ! 😊 !

[@jmflournoy386]

we used to read plugs and individual egt wish we had had 02 we used popsicle sticks xrams were tough

[@sparwars]

Two things. First..try a Ford product firing order difference. Second, is there a preventative AFR number to get some added safety? Jump the secondary jets a few? Us street guys need to know if our afr targets are hurting us.

[@sparwars]

Do you suppose a 1971 cleveland 4v iron intake was analyzed back then for even distribution? Do I trust the old engineers vs an aluminum aftermarket installation?

[@Dannymclovin]

ebay sellers have started importing these 2 manifolds without branding for 175-200 bucks on both i currently have a the dual plain on a blowthrough 5.3 and has run fine but for hood space alone i wanted to get the single since its almost 2 inches shorter than the dual

[@bethanyhaskiell9116]

Wow usually the dual plane is shorter I've never seen a dual plane that was taller than the single plane counter part

[@Dannymclovin]

@@bethanyhaskiell9116 I’m only going off part numbers but on eBay they sell both (I run an eBay 300 130 dual plain) but I’ve gone to a summit store and they have both of those next to each other and the single plain does look shorter

[@jdcarguy1242]

I'd like to see how much better something like a Parker funnelweb intake would do with distribution.

[@Go4BrokeOffroad]

Sefi for the win.

[@m.pietro9087]

Richard, I’d love if you could test the Edelbrock Pro Flo 4, specially in the Ford 302. Thank you.

[@bigrich7026]

Which cylinders were going lean? Wet flow will be worse.

[@ninjahawg94]

I think with certain engine platforms and coresponding cylinder head designs afr balancing within each individual cylinder can be acheivable with a dual quad intake or ITB's. No real difference than port injection other than better control over precise fuel metering at all rpm ranges due to electonic control. Sure there will be some minor differences due to differences in individual cylinders like ring sealing, valve sealing, dynamic compression differences, cam grind tolerances, etc., but once each cylinder has its own dedicated throttle to control and refine or tune the end result should be balanced between them. Just my 2 cents worth.

[@richardholdener1727]

a dual quad what? Tunnel Ram? dual plane? all of these still have dramatic changes in distribution. Stack injection (assuming the same runner shape and legth) can be closer than typical carb intakes. The ring sealing etc... mentioned would be a tiny fraction compared to the difference in distribution caused by the intake and attending fuel demand.

[@earth9531]

Lean Mixtures do NOT kill cylinders or motors. Cylinder TEMPERATURE does.

[@joemadoo]

Can you please do a collaboration with Project Farm. That is all! Love your content!

[@richardholdener1727]

they do good stuff

[@phillipkeep7037]

Would be interesting to test the dual plane with an open spacer for comparison

[@danmyers9372]

It tends to slightly help the distribution but not enough to overcome the inherent design issues.

[@KompressorPete]

Great test- Thanks! Could a simpler/cheaper messurement be made with a (cheap laser) temp measurement on the individual exh manifold pipes? Is cyl 1 & 7 often the most starving cylinders?

[@richardholdener1727]

no-EGT is not AF

[@blainesnider9089]

Mercruiser staggered jets may be 2 to 4 different jets, and in the carter's they used air directors and staggered jets

[@richdouche8253]

Always wondered why when the auto world made the transition to EFI, there weren't o2 sensors for each individual cylinder, as there were injectors placed for each individual cylinder?? Seems if your goal is optimization, that would have been the logical step, right.

[@chevyrc3623]

So what's making cylinder number 1 run much leaner than the rest

[@2QuickNovas]

Has anyone added injector bungs to a dual plane LS intake in order to make a broader torque curve? No one seems to sell that configuration.

[@joejohnson4868]

Do you think the lean cylinders is a product of the intake design and/or firing order. I would to see the same test on a port layout like a SBC and see the individual AFRs cylinder to cylinder.

[@ryandoyle4344]

Is it due to a runner with additional airflow, less fuel, or both?

[@bill2178]

even with efi it can still be 1-2 point variation but i expected carbs to be more consistent than efi

[@Clobercow1]

Engine Masters did multiple tests of EFI and Carb with individual cylinder AFR readings and carbs don't fuel as evenly I thought either. For that matter, neither does batch mode injection. If your really want to dial it in, sequential injection is require, though probably not necessary for a good running engine depending on how close to the edge you're pushing it.

[@johnhaskell6251]

I've wondered about larger cross section for lean ports. I've looked at Buick 455 factory manifolds noticing those manifolds are huge in cross section. Never seen a dual plane manifold that large. Just thinking.

[@petepeto9335]

Richard.. can i ask what car/truck u have... And ofcource engine? Supercharger? Cam?.. Nice vids... Just never stop making 💪 Greetings from Finland

[@richardholdener1727]

202 Silverado (all stock 5.3l)

[@keithscudder7136]

Love these tests ! Question, if you are running headers that don't have any O2 sensors in them, could you use a thermal gun to find the cooler/hotter cylinders ? Thanks in advance.

[@richardholdener1727]

temp isn't just AF-it is timing

[@keithscudder7136]

Let me guess, too little timing=more heat, extra timing = somewhat cooler. Thanks for your answer.

[@torquetwisted4294]

Richard... If you happen to see this... Could you please tell me which colors on the single plane intake graft, go to what cylinders ? It would help me in my research greatly... Thanks

[@richardholdener1727]

what are you researching

[@jeffreylynch3203]

When you say fuel injection make sure you make it clear you mean port fuel, not throttle body. Throttle body is a total waste of time, money, and effort. Still has a wet intake, for one thing.

[@richardholdener1727]

TB injection can be tuned to provide a better average AF than the carb, that is one benefit, but can't do individual cylinder, but it often makes more power than port EFI (like a carb) from the charge cooling.

[@jeffreylynch3203]

4-7 switch?

[@austincjett]

How about a real world AFR measurement at part throttle between 1,600 to 2,500 rpm. Were an engine spends the majority of it's time.

[@richardholdener1727]

how about your factory EFI constantly monitoring and altering the AF under those cruise conditions because of closed loop. You are good at part throttle

[@jesusyeshuaelelyonelshadai6295]

Is it possible to run 2 separate ecus on a 8 cylinder fuel injection motor with 4 02 sensors to monitor and regulate the efi system for maximum efficiency??? 🤔🤔 of course some wires will be spliced together inputs .. outputs would vary also.. could it be not a fuel issue but a air tunnel issue... I think by changing port size or inserting a restricted adapter in the lean cylinders might get less air and maybe more gas... to make that cylinder run same as rest..

[@TK-eg7eg]

You would just add fuel to the lean cylinder if you have EFI. Fueltec and Haltec can run 8 o2 sensors.

[@adamdubeau8038]

How would these results go if you tried the Aces Throttle Body injection to compensate for the AFR adjustments?

[@richardholdener1727]

you can help the average af but not cylinder to cylinder

[@DWBmotorsports]

Part 2 out yet?

[@richardholdener1727]

yes

[@johnb7430]

How does adding spacers under the carb affect distribution? I've always heard open spacer for dual plane helps distribution... but does it?

[@richardholdener1727]

this had a 1/2 spacer under the carb with boost (it had the fittings for the boost and BOV).

[@1clnsdime1]

That's why u have to read the plugs.

[@sktt1209]

Would be really interesting to try to jet each 4bbl hole to fix it. Would jetting a corner up help?

[@richardholdener1727]

it would change more than 1 hole

[@sktt1209]

Right just wondering if you could bandaid it at all.

[@Jim_Lawrence]

So recommendation is read the plugs along with the O2 sensors?

[@richardholdener1727]

If you have 8 sensors, no need to read plugs

[@Jim_Lawrence]

@@richardholdener1727 This is true. I meant for the "Normal" guy that has just one sensor in each header. If the O2 reads fine, maybe you detect rich and lean cylinders with a plug check. Not everyone is as cool as you with all those toys you use 😂

[@richardholdener1727]

lots of guys do that-especially nitrous guys. The other option is to put sensor bungs in each primary port and make pulls reading just 1 cylinder-then compare.

[@sevencorter]

I wonder if this has to do with each cylinder having a different flow rate/flow characteristics based on the head design and header flow concentration and o2 sensor location. Just a few thoughts.

[@Prestiged_peck]

Definitely a big part of the problem here

[@richardholdener1727]

Head design and header flow concentration and sensor location? All that and not the thing that was actually tested? How about no.

[@sevencorter]

@@richardholdener1727obviously the intake has a lot to do with it, but how much do each of the cylinders pull from the intake. I imagine it to be like a litter of 8 puppies trying to get milk from 4 tits. Some of the puppies are going to have a stronger suction and therefore get more than the weaker ones. Each primary tube has its own flow characteristics and the concentration may miss some sensors while fully blasting others. Picture it like those o2 sensor spacers to make them read less. There are plenty more factors that could affect the results of what a sensor is reading and displaying.

[@m8_fanatic]

Hey mate, looking for advice on a cam for a 350 sbc. It has standard flat tappet heads, new 4 barrel 600 holley on an edelbrock street performer. And new hei dissy. Also block hugger headers and 2.5 exhaust. Im after a cam that doesnt compromise torque and has a nice idle to it, any suggestions? Its a 66 impala. I want to make more power but not lose drivability down low

[@richardholdener1727]

look at XE256 or 262 from Comp cams

[@dfields80]

Dual carbs

[@jimjohnson3357]

Would stager jetting have an effect on the AFR for each cylinder? Also for those of us who don't have the ability to check each cylinder for AFR can we tune using exhaust gas or header temperature in conjunction with AFR?

[@bill2178]

egt is good for timing but not for afr

[@AlanRoehrich9651]

Stagger jetting works. While EGT is not ideal, it is useful, if used correctly and understood.

[@richardholdener1727]

stagger jetting works best on tunnel rams (8 jets and 8 cylinders, but it can help on single planes

[@johnlewis8156]

Do sbc intake manifolds have the same issue? I am putting an old LT1 in my wife's 240z with a T56 but planned on shooting a little N2O for when she has a bad day. But I guess I will keep away from the bottle so that it doesn't do that.

[@richardholdener1727]

small shots are fine

[@johnlewis8156]

@@richardholdener1727 it's amazing how many motors are out there right now with this happening and they still survive.

[@kevinvannoy]

i need to bring your blow thru carb back.. 😉

[@richardholdener1727]

Yes

[@kevinvannoy]

it’s there.. 👍🏻

[@TomSmith-cv8hk]

Where's the other two cylinders traces ? and if you number them we may see what causes the dual plane unevenness.

[@ztwntyn8]

I tried a single plane holy street dominator on my 400 Pontiac. It lost lots of torque below about 3000-3500rpm it sucked for the street. With gears more cam and higher stall speed I’m sure it would work ok but I had none of those things

[@Carl_Jr]

Yes. That matters. I went from a dual plane Weiand to a Victor Jr on my 350 and love it! But I also have a 3,000 stall converter in my 71 Camaro. Without it I doubt I would be as happy

[@markh8301]

So at what number is AFR considered lean? Guess it's a lot less than stoich

[@richardholdener1727]

above 13.0:1 is lean at WOT (or even a number below that that causes detonation)

[@malamri424]

wow this is unexpected! another argument for going with a rich AFR.

[@NBC_NCO]

Do equal length runners help?

[@richardholdener1727]

they can help to equalize flow and charge filling to the cylinder

[@davidphillips3953]

Look behind you! There a funny looking bald guy sneaking up back there around 9 minutes in

[@daledavies2334]

What was the AFR on cylinders 4 and 6 with the single plane manifold?

[@richardholdener1727]

6 was 10.5-11.4 and 4 was 10.5-11.7 variations at different rpm

[@daledavies2334]

@@richardholdener1727Thank you Richard for the quick response. So richening up the jets on that side of the carburetor is not exactly feasible. Needs some work probably in the manifold plenum to equalize the fuel distribution. Throttle body injection would not cure the problem. Only port injection could effectively deal with it, but the airflow discrepancies could have it off a bit.

[@keithswiercz3890]

Would port injection help with this issue?

[@richardholdener1727]

with individual cylinder trimming it would

[@johnnijssen8590]

I just watched your AFR video. Those lean cylinders would keep me awake at night. I wonder if a TBI would fare better than a carb? As I understand it, a TBI tries to throw the same amount of fuel in every cylinder, but vacuum pulling on the venturi of a carb will be a little different for each induction stroke. I put a TBI of a SP manifold on a Pontiac because other test I read about suggest TBI prefer SP manifold over DP. However, I call BS, all I need do is look at your manifold test and focus on Tq under 5000RPM. Still, all said and done, how do we fatten up that one cylinder? I'd try fooling around with a turtle, but with low optimism.

[@richardholdener1727]

maybe porting, corner jetting, rotating carb etc...

[@johnnijssen8590]

That reminds me. I had a 540BBC making 700Tq on the dyno and looking at the AFR on each side I saw a difference, so I tried corner jetting. It did help even the AFRs, but the power output remained the same. Then some other engine builder told me he noted a loss of power when he tried to even things out, so I just forgot about trying to do that. I once checked each cylinder's AFR on a stack EFI system I built. I use one O2 sensor and measure each cylinder one at a time.

[@richardholdener1727]

Watch the EFI video where I did individual cylinder tuning-it changed power very little-but did make it safe

[@HioSSilver1999]

That thing needed to rev higher

[@alexbrown4820]

With a solid cam, is it possible to adjust this with valve lash? Or am I way off?

[@richardholdener1727]

it won't change the intake issues, but would be interesting to see how it changed AF

[@alexbrown4820]

@@richardholdener1727 I learned something I thought was odd recently. I did a compression test on my friends mud truck. It's about a 14 to 1, 602ci chevy with a good size cam. No 2 cylinder had a lot more pressure. Reset all the valves and that cylinder had a lot of slop. Reset everything and all was back to the same. That's the reason I was curious

[@richardholdener1727]

If you increase lash, you effectively reduce the cam timing (make it milder), this increases cylinder pressure

[@alexbrown4820]

@@richardholdener1727 that's very interesting. Intake exhaust overlap?

[@JC-gw3yo]

good grief... Looks like going to EFI is the smart thing to use

[@scottm7341]

120° LSA? Why? That will prevent the headers from doing anything useful. Heck it shouldn't even exist.

[@richardholdener1727]

headers still function with 120 lsa

[@Bulkshit]

Interesting but, you should rehearse the dialogue first. For someone like me who depends on the cc, It frustrating, to say the least. Mark

[@user-vn5yq7bu9q]

Sure looks like an intake gasket leak on the single plane

[@TomSmith-cv8hk]

Single plane it's the adjacent runner openings into the plenum with intake valve opening overlap that miss out. 3 robs 1 and 8 robs 7. kzbin.info/www/bejne/q4faZHqvict7oqc

[@dannypitts2442]

I see talking about green screen on live worked you got pic up there @Richard Holdner

[@gothicpagan.666]

On much smaller engines that I get to work on, 13.2-13.4 AFR is normally where the best power is. In all honesty there has to be a better inlet manifold available than what was tested. Realistically either of those is unusable.

[@richardholdener1727]

13.4? lean

[@gothicpagan.666]

@@richardholdener1727 Everything has to be pretty much spot on. The right squish, dynamic CR 8-8.5:1, 102+ octain, coolant temp >86Deg C. On and on. The risk of melting a piston is always there, even engine rpm has to kept above peak torque for extra reliability. Needless to say I've had a few failures over the decades 🤤🙂

[@user-by1io4fq3j]

Too lean, too long, too bad. Priceless.

[@bobqzzi]

Take away: don't run carburetors.

[@richardholdener1727]

the carb is not the problem-would be the same with port efi

[@bobqzzi]

@@richardholdener1727 Except you can fix it with EFI pretty easily. Of course, you could run a tunnel ram or Webbers and it would fix it as well.

[@Prestiged_peck]

And this is why you run multiport injection...

[@imtheonevanhalen1557]

Can you say PORT VELOCITY??.......all of that yadda was just summed up. Street cars, dual plane...circle track WFO, single. And I'll say ALL of the lore of the Hemi is complete BS....ALL of the pro-stock Mopars ran wedge engines.....period.

[@dominicanwar363]

EDELBROCK = a few red faces I bet.

[@richardholdener1727]

this is a function of a single plane and dual plane design-not just Edelbrock

[@dominicanwar363]

Thanks, I had no idea that air distribution was so bad. I had a V8 (back in the day) but it had individual carbs. Are OEM manifolds just as bad?