RPM Air Gap

[427fan]

Does anybody know why edelbrock hasnt made a single 4 rpm airgap?

[Pentroof]

Their thinking may have been that the FE hobbyist is more likely to go with bling and wow factor, and therefore tooled for the 2x4. The factory dual quad look is very popular in the Ford camp, so why not target that? Vic just doesn't understand that most of us would prefer Holleys under our lid.

I don't believe the 2x4 is selling very well, so my guess is they won't follow up with a single four.

I will say, I bet that dual quad air gap has nice street manners for a street rod or cruiser. I just keep thinking GM when I look at those Carter copies and I can't get get over it.

[jayb]

I guess the other thing is that the normal 4V RPM intake works so well, I'm not sure how much of an improvement there would be if it were to be redesigned as an Air Gap intake.  The 2X4 Air Gap intake didn't do that much better than the standard 4V RPM in my testing, so the benefits of going to an air gap design on that intake may not be all that pronounced.

[rcodecj]

I'm not sure how they would do it, but on the 385 series motors, the RPM air gap has larger runners than the regular RPM. Otherwise there wouldn't be enough difference for me to justify buying another manifold.

[482supersnake]

You could always build one yourself This was made from a Victor and an eboss 351 intakes and sits a little higher than a victor. Now i just need someone who can Tig weld aluminum. Scott

[machoneman]

Wow, that is ambitious! Good luck. 

[rcodecj]

How in the world can the 351c ports match up to an FE so well?
That's amazing.

[machoneman]

Garrett still sells the old PSE designed adapter that allows any Cleveland intake to fit an FE.

http://www.garrettmachine.com/

[jayb]

Garrett still sells the old PSE designed adapter that allows any Cleveland intake to fit an FE.

http://www.garrettmachine.com/

Is that really true Bob?  What I read on their site is that they have an old PSE manifold available, but it is rare (read expensive).  They also show how they can modify an Algon FE intake to turn it into a similar adapter intake (also expensive, I'm sure).  But I didn't see anywhere that they had a PSE type casting available at any reasonable price.  Did I miss it?  I haven't called them to ask...

[machoneman]

Jay, my apologies and you may be right. I hadn't really read the posted text this time around, having seen it before some years ago. Now on review, they are seemingly talking about a single old PSE adaptor they have (or had) in stock for sale. What also threw me were the pics just below that show the Algon intake mod. As you said, pricey, I'm sure

Still, it's an interesting piece of lore, one that I'm sure you'd like to try if somebody can get their hands on one.  Interesting too in that today a handful of very late model, very high flow, single plane, 4-bbl 351C intakes (and I do mean tall!) are readily available from CHI, other Aussie suppliers like Parker and methinks World Products, Ronkonkoma NY.  'Course I'm equally sure you have at least pondered doing some similar machine work on a donor FE intake, eh?    

http://www.chiheads.com.au/3v_manifolds.php

[mmason]

How about a RPM mounted on a Dove manifold.

[jayb]

Yikes, look at all these custom intakes!  I'm going to need to write a whole new book 

I have actually been giving some thought to manufacturing some intakes that are similar to the old PSE design.  There seems to be a lot of interest in those, plus there are some really good small block intakes out there now (like the CHI intakes).  The PSE intake setup did real well in my dyno tests, so obviously this can be made to work.  I have developed a connection with a local CNC machine shop, and they have a local casting company they work with, so I may end up pursuing this after I get done with this year's Drag Week thrash.

[482supersnake]

Something like this would be cool http://www.jegs.com/i/AFR-Airflow-Research/033/4801/10002/-1?parentProductId=1434029

[machoneman]

Yes, those are pretty neat and have multiple benefits. See Tony Mamo's (AFR's chief tech) notes for this same design of intake from Speedtalk:

 AFR TITAN SBC Intake manifold
by Tony Mamo @ AFR » Wed Dec 01, 2010 7:20 pm

Guys,

Truthfully we are a bit surprised at some of the responses regarding this as it has been a big hit with dyno operators, trade show customers and engine builders, as well as the various media outlets that have seen and tested them. But we understand ground breaking new products can always be met with some skepticism. Hopefully the following will clear up some of the concerns and questions.

1 – Part #4801, our single plane 4150 flange race manifold made 15 HP and 15 ft/lbs of torque over a leading competitors similar manifold. Part number #4803, our single plane street/strip intake picked up 7 HP and 20 ft/lbs of torque @ 3500 RPM.

2 – These intakes are half the weight of aluminum....A ten pound weight savings up high and off the nose of the car.

3 – The runners and plenum of our composite plastic manifold ran 30 degrees cooler during our many dyno testing sessions also reducing the temp of the carb body as well….cooler air/fuel equals HP.

4 – These intakes feature re-usable OEM quality rubber Viton seals which do a much better job sealing than paper gaskets (with none of the scraping and clean up mess upon disassembly). A rubber O-ring distributor gasket is also included….SB Chevy's notoriously weep oil in that area.

5 – Interchangeable runner configurations (spider) to a common valley plate. No need to mess with ignition timing (no distributor removal required) or breaking of the water seals. A 4500 carb flange version is coming soon which we feel will be very popular in drag race applications.

6 – Dual distributor hold downs and cast in nitrous bosses.



SchmidtMotorWorks wrote:

If you like vacuum leaks though, enjoy.


We have invested three years in the design and testing of these composite manifolds and have done some field testing for 18 months prior to the news of this new product being released to the public….. they do not leak.


SchmidtMotorWorks wrote:
TERRIBLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Plastic is good for some things, performance manifolds is not one of them.

That looks something like what Wilson was working on some time ago, no surprise they still don't have one on the market.
Maybe it is a continuation of the same project and Wilson wisely gave up on it.

Even if plastic could be made to work in that application the design is terrible, four corner screws to hold that thing together without leaking??     

In the end though, one has to ask, why do this in plastic at all? Love of plastic? Cost of manufacture? Disregard of quality?


The runner configuration (spider) is attached with TEN bolts not four! (Six 6mm bolts and four 3/8-16 bolts in the center). We are compressing a void volume viton rubber seal, not a paper gasket. The owner of the company we hired to help us with this project ran the GM plastic intake division for many years and his partner ran the Ford plastic division for many years also. Together they have over 30 years of plastic intake manifold experience. Their facility has performed destructive testing on the AFR manifolds that simulate 100,000 miles of usage in a vehicle, the same testing procedure OEM’s use to qualify new parts. In fact they are a consultant today for many of the OEM’s and provide some of them with product.

In our opinion plastic is one of the ultimate choice of materials for an intake manifold (see the reasons noted earlier in this post), and it would have been far easier and much less expensive to simply cast a better flowing piece in aluminum....we decided to manufacture something far more innovative in spite of the design challenges and how costly it was to do so.

I would encourage anyone interested in picking up the latest Engine Masters....its a very informative article with lots of photos and detailed information.

Retail on the complete intakes (runner configuration of your choice and baseplate) is $599.....the spiders themselves will retail for $395

AFR P/N 4801 is available now (the 4150 race piece), with the lower plenum height street/strip version not far behind and the dual plane configuration available in the spring of 2011. Be sure to stop in at the AFR booth at the IMIS or the PRI tradeshow to see them in person.

Thanks,
Tony Mamo
AFR R&D / Product Development Mgr.
661-705-8508
Tony Mamo @ AFR
Pro

 
Posts: 267
Joined: Tue Nov 07, 2006 1:23 pm

[482supersnake]

If I was to do a new PSE base my first choice would be Buddy Bar Manifolds. I think they do all of the Blue Thunder stuff and saw a show on I think the Science Channel where they were at the factory casting intakes for Mopar. I wounder if they did the intakes for PSE?. They might still have the molds if they did. Also I would be willing to offer up my manifold to you Jay if it would help the process as it will be awhile before I need it. Scott