Performer
Burning Brakes
Joined: Oct 2011
Posts: 956
Likes: 86
From: McDonough Georgia
ANYWAY, when I stated that all these manifolds are the same, I am basing it on this hot rod article, showing the differences are very minor and possibly undetectable by seat of pants driving, which is all I intend to do. No racing, no drag strips,etc. As I have said before, all I want is a relatively strong engine, without going to extremes, and without a bunch of sacrifices i.e. cold air intakes, big carbs, even to the point of different fuel lines, different throttle cables (hate those Lokar units), and even drop base air cleaners.
'
Its all relative.
'
Its all relative.
If you have the clearance go with the Edelbrock RPM 7104. There is no other choice.
501 peak torque, 465 hp
You could downgrade to the straight Performer 2101
494 peak torque, 456 hp.
The 2601 air gap spreadbore will give you:
504 peak torque, 458 hp
Performer RPM air gap 7501 (this is what I run) with square bore will net you:
508 peak torque, 474 peak hp
Performer RPM 7101 square bore gets you
504 peak torque, 470 hp
You can only get the most from your setup with the Performer RPM. To get more you have to go squarebore.
IMHO the loss of HP with the 2601 isn't worth it.
Thread Starter
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Down to:
Performer RPM Quadrajet OR Performer Air Gap (non-RPM)
I will never push RPM past 5500. The Air Gap actually has better torque at 3000 and better peak torque than the RPM, so makes me think its better for me. I could care less what happens at 6000 where the extra HP is made.
Just a little worried about colder weather problems with Air Gap.
I did talked to Edelbrock and they claim that the runner design of the Air Gap is improved over the 2101 Performer?? The port dimensions are identical.
Performer RPM Quadrajet OR Performer Air Gap (non-RPM)
I will never push RPM past 5500. The Air Gap actually has better torque at 3000 and better peak torque than the RPM, so makes me think its better for me. I could care less what happens at 6000 where the extra HP is made.
Just a little worried about colder weather problems with Air Gap.
I did talked to Edelbrock and they claim that the runner design of the Air Gap is improved over the 2101 Performer?? The port dimensions are identical.
Last edited by Shovels and Vettes; Feb 25, 2015 at 09:13 PM.
Burning Brakes
Joined: Oct 2011
Posts: 956
Likes: 86
From: McDonough Georgia
Down to:
Performer RPM Quadrajet OR Performer Air Gap (non-RPM)
I will never push RPM past 5500. The Air Gap actually has better torque at 3000 and better peak torque than the RPM, so makes me think its better for me. I could care less what happens at 6000 where the extra HP is made.
You will have to measure, but I do not believe the air gap will fit under your stock hood even with a drop base air cleaner.
Just a little worried about colder weather problems with Air Gap.
I have never had an issue. Starts right up and idles perfect. I have an electric choke.
I did talked to Edelbrock and they claim that the runner design of the Air Gap is improved over the 2101 Performer?? The port dimensions are identical.
It is a limitation of the small front venturis and squeezed front intake on a spreadbore
Performer RPM Quadrajet OR Performer Air Gap (non-RPM)
I will never push RPM past 5500. The Air Gap actually has better torque at 3000 and better peak torque than the RPM, so makes me think its better for me. I could care less what happens at 6000 where the extra HP is made.
You will have to measure, but I do not believe the air gap will fit under your stock hood even with a drop base air cleaner.
Just a little worried about colder weather problems with Air Gap.
I have never had an issue. Starts right up and idles perfect. I have an electric choke.
I did talked to Edelbrock and they claim that the runner design of the Air Gap is improved over the 2101 Performer?? The port dimensions are identical.
It is a limitation of the small front venturis and squeezed front intake on a spreadbore
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Performer: 4.05
Performer Air-Gap: 4.32 (0.27" taller)
Performer RPM (air gap or no): 4.72 (0.67" taller than performer)
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
With my 77 and the Performer (2101), stock air cleaner installation, I have room for 3/8" under the carb and 1/8" clearance from the hood.
So total 1/2" with no clearance.
So an airgap would fit but I could not get an insulating 1/4" carb gasket under the carb and still have clearance.
So total 1/2" with no clearance.
So an airgap would fit but I could not get an insulating 1/4" carb gasket under the carb and still have clearance.
Last edited by REELAV8R; Feb 26, 2015 at 12:20 PM.
Thread Starter
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Performer RPM
My only question for you is do you think the drop base restricts the airflow into the inlet. A previous post said you need at least 3/8 from top of vent tube to roof of air cleaner lid. Other forums and posts suggest that airflow can be restricted with a large drop base air cleaner. What do you think?
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Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
BK, did you say you are using the K&N drop base? I have a factory drop base, this its the unit made for the L88 hood setup, got it a Carlisle. It has a pretty significant.
My only question for you is do you think the drop base restricts the airflow into the inlet. A previous post said you need at least 3/8 from top of vent tube to roof of air cleaner lid. Other forums and posts suggest that airflow can be restricted with a large drop base air cleaner. What do you think?
My only question for you is do you think the drop base restricts the airflow into the inlet. A previous post said you need at least 3/8 from top of vent tube to roof of air cleaner lid. Other forums and posts suggest that airflow can be restricted with a large drop base air cleaner. What do you think?
Thread Starter
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
No doubt
My drop base is a cheap generic unit, about 1.5 inches deep. I'm not sure of the vent tube to lid clearance (I am using a Qjet). But based on the way the car runs, as good as 12.15 at 110mph in the quarter with the air cleaner on, I don't think its starving for air flow. It will run up to the 5,800 rpm shift points with no drop off in power.
Thread Starter
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Air Gap
Down to:
Performer RPM Quadrajet OR Performer Air Gap (non-RPM)
I will never push RPM past 5500. The Air Gap actually has better torque at 3000 and better peak torque than the RPM, so makes me think its better for me. I could care less what happens at 6000 where the extra HP is made.
You will have to measure, but I do not believe the air gap will fit under your stock hood even with a drop base air cleaner.
Just a little worried about colder weather problems with Air Gap.
I have never had an issue. Starts right up and idles perfect. I have an electric choke.
I did talked to Edelbrock and they claim that the runner design of the Air Gap is improved over the 2101 Performer?? The port dimensions are identical.
It is a limitation of the small front venturis and squeezed front intake on a spreadbore
Performer RPM Quadrajet OR Performer Air Gap (non-RPM)
I will never push RPM past 5500. The Air Gap actually has better torque at 3000 and better peak torque than the RPM, so makes me think its better for me. I could care less what happens at 6000 where the extra HP is made.
You will have to measure, but I do not believe the air gap will fit under your stock hood even with a drop base air cleaner.
Just a little worried about colder weather problems with Air Gap.
I have never had an issue. Starts right up and idles perfect. I have an electric choke.
I did talked to Edelbrock and they claim that the runner design of the Air Gap is improved over the 2101 Performer?? The port dimensions are identical.
It is a limitation of the small front venturis and squeezed front intake on a spreadbore
The 2601 manifold is like a 2101 Performer, but with Air Gap. In the Hot Rod reports, it actually does better than the RPM QUadrajet in terms of Peak Torque and Average Torque, it loses out slightly in Peak HP, but I am very skeptical that this is accurate, because I can't figure out WHY it would be better. The port dimensions are identical to the 2101, the height is only .25 inch taller. So whats the magic? I question the dyno runs, did they allow the engine to fully warm up, and when it does, and the manifolds are hot, do the numbers still do as well?? Logically, I can understand the Air Gap concept, but can it really make more torque than an RPM manifold in the same RPM range....and will it maintain than when fully warmed.
Last edited by Shovels and Vettes; Feb 26, 2015 at 05:49 PM.