Jay or anyone else, PI intake

[My427stang]

Have you ever used an alum PI intake north of 550 horsepower?   Brent is currently building us a nice set of BBMs for a real deal 4.30 geared 4 speed 68.5 CJ coupe which will end up as a 462 or so inch stroker.  The factory air cleaner needs the proper carb location and we are trying to do it period correct.

We have one that of course we can sell to get something better, but it would be nice to use it with a little rubbing.  Any experience at higher horsepower levels?

Joe - what do you think?

[CaptCobrajet]

I've done several Stockers that go north of 550 with the 481/490 and 525 lift rules.  I think the manifold could make 600 hp if you suck on it hard enough, but that may be about the limit.   It will respond to porting in the right places, but without working it, it will struggle to get past the 600 mark.

[My427stang]

Thanks Blair! 

If we use it, we'll be sure to clean it up a little to take the edge off.

[Joe-JDC]

Should be possible.  If you work on the ports, then I suggest you make them as tall as possible to match the heads, and blend the inside turns to the heads on all ports.  Since you mentioned the BBM heads, then a gasket match is probably ok.  Try to open the width of the port between the pushrod tubes as much as possible without breaking through, and blending in a gentle radius out to the BBM port size.  There is some to be found in the plenum if you can use a large carbide to smooth the radius around the corners of the port entries.  I have seen the PI pick up 37 lbft with minimal work over a so called ported intake, so anything is possible with careful work.  Joe-JDC

[jayb]

On my 427 dyno mule Joe's ported PI made 540+ horsepower, and the best combination made 600 on that engine.  If you build the engine for it, Ross, I don't see any reason why you couldn't get 550+.  You are going to give away a lot of power compared to other intakes, but if you want to stay period correct, I'm sure you could do it - Jay

[My427stang]

On my 427 dyno mule Joe's ported PI made 540+ horsepower, and the best combination made 600 on that engine.  If you build the engine for it, Ross, I don't see any reason why you couldn't get 550+.  You are going to give away a lot of power compared to other intakes, but if you want to stay period correct, I'm sure you could do it - Jay

I am going to have to get some measurements with the CJ air cleaner...period correct is a factor but having the early style CJ scoop line up during street use is really the intent.  I'll have to see where the car pad sits and how much wiggle room we have.  This motor will be done pretty fancy and giving up 10-15 hp is one thing, but if its a 50 hp bill, we may have to come up with something else.

Jay does your book have dimensions of all the intakes? 

[Joe-JDC]

Ross, I would port match a RPM, and remove all lettering off the manifold so that it looks like the ford intake.  The Streetmaster is short at 5.875", RPM 6.0", PI 6.375" at rear pads.  The CJ iron is 6.0" so, you have a choice.  The BT is tallest of the dual planes 6.750".  I have removed the lettering on several intakes, and hit the area with a sand blaster, then painted to look stock.  It becomes difficult to really tell the difference if you want it to look period corrrect.  Joe-JDC.

[jayb]

Jay does your book have dimensions of all the intakes?

Yes, the book has the height, runner volume, and carb setback for all the intakes tested.

[My427stang]

Thanks guys

Jay watch for an order, sounds like you have all the info I need. 

[My427stang]

Jay, you should have an order sitting there.

Thanks

[jayb]

It'll go out today, Ross.

[My427stang]

Thanks Jay!

[Clark Coe]

Ross,
I could get FE Streetmaster intake measurements for you.....carb is still removed.
If you are still in the Omaha area, you are welcome to come out to Elkhorn for a look.
Notice that I have removed the Edelbrock – Streetmaster from the manifold.
Clark

[Joe-JDC]

Those measurements were in my post above.  The Streetmaster is one of the shortest performance aluminum intake.  I think a ported streetmaster and a 1" supersucker style plastic spacer would be one of the best intakes for all around street/strip use.  Joe-JDC

[My427stang]

Thanks guys!

We are going to look close at the measurements in Jay's book and then make a call

Got some time before the motor goes together, may even machine and port a Victor for it if he decides to go away from stock look

[Qikbbstang]

Joe with your porting knowledge and experience few have the unique insight you have on intakes. Just wondering, Jay's book showed the Holley Street Dominator to be in a real neck and neck horse race with the Edelbrock StreetMaster. Per your recommendation is it the rarity/lack of Street Dominators that have you not mention them in the same recommendation as StreetMasters or do you feel that  StreetMasters are superior to the Street Dominators?
   I've always been fascinated  by the unique diagonal runner design of all StreetMaster intakes be they (Ford, Chevy, Mopar, Pontiac etc) and why Edelbrock only utilized that unique runner design for a limited time - never to be offered again.

[Joe-JDC]

I have acquired 3 Streetmasters, and 3 Street Dominators which I am in the process of porting to different flow numbers and balancing the ports so that I can keep them fairly close in flow.  I want to have 1ea flow about 20cfm over stock, 1ea 50cfm over stock, 1ea maxed out, and then do a dyno test to see what the differences will be between them, and if on a given engine, what airflow difference in the manifold does to horsepower potential with the same heads, camshaft, cubic inches, etc. Then,  hopefully,  this will be also a chance to compare that same PI in Jay's book against a RPM on the same engine.  Joe-JDC

[Qikbbstang]

StreetMaster's and Street Dominators are so cool in that they were released during the gas shortage and advertised for use on RVs.  Never will forget the boost a stock StreetMaster made on a mild RV-cam'd 351M I had. Never dreamed an intake could make such a difference and the difference was across the board. Since you mentioned comparisons SM vs SD over stock how do the cfm's  compare in stock forms?