Super Victor vs RPM Airgap Dyno results SBC

[Troy Patterson]

gmrocket i agree with you 100%. But i have some riff raffs in here telling me that i am crazy that the Dual Plane RPM didnt out perform the VIC. Well you prove my point too, well said. I will never be convinced that single plane Vic is the overall better intake for winstons combo. I know a guy who will never use a single plane intake for his combo again. He has tried the single, but the dual plane pulled quicker everytime for his 7,000 RPM 427 69 Camaro with a 4.30 gear.

You know, the carburetor design / calibration and fuel curve are all to important to the style of intake to make a single plane vs. dual plane comparison without optimizing the carburetor(s) for each. If this isn't done, it's really which manifold design happens to be better suited to the "present" tune and carburetor bolted on top it. This is akin to the guy who bolts a dozen carburetors on his engine to see which one runs the best without regard for jetting, mechanical or vacuum secondary operation, etc.

Troy Patterson blog tmpcarbs.blogspot website TMPCarbs.net Engine Professionals Magazine's TMP Tuning article, pg. 44

[Winston Wolf]

Good point Winston. Taking the car to the track and comparing manifolds is what i want to see. Sure the dyno says the Vic makes more horsepower, thats fine. But i want to see a real world physical comparison on these manifolds on the strip. This is the true test. A good dual plane will like more carb. The test i would like to see is the ET comparison vs the RPM this engine is shifted at. I am talking 6000 rpms, 6500 RPMs, 7000 RPMs. Then we can say what manifold out performs who in that particular RPM range.

I keep good records of shift points on my LM2. With the RPM Airgap, I was shifting so the car would change gear at exactly 6500 RPMS and it would trap around 6600-6700, which after dynoing it at the end of the year, was probably over-reving it. It was turning 11.7's at from 115.5 mph to 117.03 mph. (btw, this is a 70 Monte Carlo)

I want to keep the testing as consitant as possible, so I'm going to leave the shift points exactly the same as last year for comparison. My point of this whole thing was not to try and maximize HP or low end response by changing carb sizes and totally retuning everything, I just wanted to see if a Super Victor (with port work) is better than an Airgap with runner work and no other changes on my build. I have enough gear that low end torque isn't an issue.

i'm still not convinced the RPM was put to shame by the VIC. here you say the RPM did a best of 117.03 which is better than the VIC has done to date,,the RPM also wins in the best 60' , best 330. the VIC wins at mid track but i have to see where that counts as a win.

in one of your runs with the VIC, all of the et's and mph are slower than the other two runs by the VIC, yet this run has the best MPH?? thats a strange one i cant figure out.

i also think that at 406" the RPM is past its peak power by a few hundred rpm due to the fact it just cant feed that many inches&thats proven by the dyno sheets. try short shifting it some time and see if it helps..maybe 6400.

I want to clear up those comments so the comparison is kept legit and fair. The runs of 117 mph with the RPM where in early September. I went back and looked at my slips from each day at the track. That day my average MPH was 116.73 and average ET was 11.856. After that day I blew a trans and had my converter changed from a 3400 stall to a 4000 stall. The runs after the converter swap, in October, saw the MPH drop to 115.53 with average ET of 11.775 The difference is the converter (a bit quicker, but lower MPH). It is only accurate to compare numbers using the same converter.

I have a full set of air bleeds and will be back at the track on June 11 to dial in the carb and see if I can squeeze some more out of it. I have also put a plenum matched 1" open spacer on it, since I was using one on the dual plane also.

And again, I don't care what the outcome is. I don't have a problem running either manifold, I am keeping them both, and will run the fastest one. I can't really tell the difference in driving the car on the street, so that isn't an influence in my decision at this point.

[gmrocket]

gmrocket i agree with you 100%. But i have some riff raffs in here telling me that i am crazy that the Dual Plane RPM didnt out perform the VIC. Well you prove my point too, well said. I will never be convinced that single plane Vic is the overall better intake for winstons combo. I know a guy who will never use a single plane intake for his combo again. He has tried the single, but the dual plane pulled quicker everytime for his 7,000 RPM 427 69 Camaro with a 4.30 gear.

You know, the carburetor design / calibration and fuel curve are all to important to the style of intake to make a single plane vs. dual plane comparison without optimizing the carburetor(s) for each. If this isn't done, it's really which manifold design happens to be better suited to the "present" tune and carburetor bolted on top it. This is akin to the guy who bolts a dozen carburetors on his engine to see which one runs the best without regard for jetting, mechanical or vacuum secondary operation, etc.

Troy Patterson blog tmpcarbs.blogspot website TMPCarbs.net Engine Professionals Magazine's TMP Tuning article, pg. 44

are saying that if its jetted different per corner on the DP it may even make more power?

i just read through the july 2011 PHR magazine and it has a dyno test on three brand new composite intakes by AFR. this is an up to date dual plane vs two up to date single planes...the DPR dual plane is considered a street/strip, the TXS is a street/strip single plane and the TXR is a race single plane.

if these three intakes where in the EMC,on this same engine, the DP would have kicked the two single planes a#$$*s

here are the results...

DPR avg TQ 459 avg HP 420 for 2362.9 points WINNER

TXS avg TQ 450 avg HP 415 for 2325.3 points

TXR avg TQ 444 avg HP 419 for 2319.9 points

the DP is 37.6 points ahead o fthe "street" single plane&43 ahead of the race single..that would be something like 10 or 15 positions,,,roughly.

i just wish these intake manufacturers would stop making these poorly desiged dual planes that dont make any TQ or HP compared to them ultra high tech pretty single planes.

if my math is wrong, please dont tell me

who will be the first to bash this magazine test?

[Matt Gruber]

AFR makes a state of the art dual plane, and yes imo it could do even better with stagger jets and a proper size carb for a DP(larger).
And for the drags a removable divider would be nice. Cut down is too cheap for $600

[Enigma]

13 pages. Seriously?! C'mon guys. Hey......let's get to the carb/efi debate now! I could waste another 30 minutes of my life instead of picking my toes or some other important task. Matt, for all your screaming about "that cut down divider is killing it", not a single one of the airgap intakes (eddy,weiand, pp, it the summit knockoff) has a cut down divider for the small chevy. Mr. Sherman, thank you for mentioning that a dual plane will always want a larger cfm with no loss in atomization due to the extra flow. That's the bonus of the dual plane. Those of us who drive our vehicles more on the street have to make concessions towards streetability and more refined manners. Enter the dual plane. The only thing an intake does is direct the signal from the cylinder to the carb, and the a/f emulsion from the carb to the cylinder. Nothing more. And within their families (sp, dp, tr, cr), truth be told the only REAL difference between them is how strong you want/ need that signal to be at what point in your predetermined rpm range and how well you want the emulsion to be delivered in said rpm range. Sure, they can all be finely tuned and tweaked, and they can be made to work outside their realm of design. But there is a category of vehicle, usage, preference, and necessity for each family of intakes. Read vizards article where he tested a bone stock rpm airgap against the best fully ported, welded, flowed single plane that kieth Wilson could build. The rpm beat it hands down up to 4500, stood right beside it to 6500, and only marginally fell off from 6500 on up past 7200. Does that make it a race manifold? No. Sure makes it one hell of a fine compromise for someone who drives mostly on the street but like the occasional 1320. On a more track oriented vehicle.....of course the single is a better choice. You guys simply aren't concerned with the compromises that we are. And that's perfectly fine. Two more words on a final note here............bob west.

[408 Nova]

This is a super old post, but....did it ever go anywhere?

[1980RS]

This is a super old post, but....did it ever go anywhere?

Yes it would be interesting to see what both do at the track. My old SV ported went really well so good in fact it made my car a tire smoker at the track. My 358 pump gas engine with a 300-25 went pretty good but was not worth that much over my ported 300-36. Now I have a ported Air Gap on the engine with the divider cut down. Will be interesting to see the results later this year.