TPI intake vs other stock intake manifolds...

[Guest Jeff Rimmer]

I've been reading through the various literature I have purchased, and am currently wondering what successes may have been obtained using the TPI intake vs other stock affordable GM intakes. I currently have a carburated setup, but for efficiency, and possible power gains, I was wondering if TPI is the way to go.

 

I surely cannot at this time afford a setup such as the Edelbrock performer EFI system of the Lingenfelter Super Ram intake system, but how comparable can the TPI system be?

 

With a 383 setup is a TPI system practical?

 

JR

 

"If your upside down and burning, you know you've gone too fast."

[fl327]

stock tpi has breathing issues over 4800

[BLKMGK]

Short answer? No way! The base was designed for 305 motors and on a 350 they run out of breath early. On a 383? I wouldn't try it and expect much.

 

However, all is not lost. Have a fabricator weld bungs and create standoffs for fuel rails in your current aluminum carb intake. Purchase or fabricate an aluminum elbow and then run a Ford throttle body on it or use one of the carb type throttle bodies. Add an ECU, some programming, and you're good to go. Force-EFI.com (think that's it) can do this conversion and custom burn a chip for you too if you'd like. It's still not a budget solution IMO but a 383 has some decent breathing requirements that you'll have to feed one way or another...

 

P.S. This is what I'm doing. $200 for the bungs etc., $100 for the elbow. Looking for used TBs on th eMustang boards and I've already gotten a used pump, filter, and a deal on a regulator. Yet to gather is a set of 30lb injectors and an ECU. IF yuo wanted to you COULD use a stock Ford EEC-IV, calibrated MAF sensor, and other parts to run this. I don't know how well this woudl work but I've been told by EFI guys that it can be done. The distributor is the only part I'm not sure about getting setup.

[Guest Anonymous]

Yeah, Len's right. With a stock TPI its long runners are for tuned for torque but its long runners aren't ideal for upper rpm power. I believe thats why they went to the shorter runner design of the vette engine a year or so later?

 

Using siamesed runners and porting (extrude honing) the intake probably would help, a big throttle body and it probably would support the engine ok, but something with shorter runners and more air flow would be even better IMHO. Depends on what sort of RPM your 383 is built to run.

 

Regards,

 

Lone

[fl327]

by the time you modify the tpi enough for good top end, you would have enough or more than enough to go with an accel unit. it would be nice on a nice stock 350 though, good driver.

[Guest Anonymous]

you know I wanted to use the TPI off a vette too but also fear not enough flow. I am going to try to find a big block throttle body off a chevy in the early 90's and mount to a Victor Jr. Sure would be cool to make a TPI out of a Victor though. Sound like a lot a guess work. Maybe I just am a little afraid to dive in.

[BLKMGK]

Head over to ChevyTalk forums and get into the EFI area. There's a Holly engineer over there who knows this stuff cold! There are some Holley intakes coming out that may interest you including a tunnel ram looking one Also, price out what the current Holley EFI intakes run - less than $500 including rails and they're already setup for injectors. A throttle body would still be needed though so some fabrication or additional dollars would be needed. Their ECU (Commander) is VERY nice if you're looking to NOT spend a million bux IMO.

[Guest Fast Frog]

Jeff:

 

A TPI setup with a 383 or even larger is very practical and expensive!! I've got a 383 in my 76Z with an aftermarket TPIS 1000cfm mini-ram injector manifold with an Accel DFI engine mgmt system. It's very efficient and works great!! I even ran a Paxton SC with it until a yr ago. I'm going to use the same sys when I upgrade my engine next yr to a 400+ci sbc with a bigger cam. But, again, my setup is aftermarket! And like BLK MGK says, a stock GM TPI manifold off of a 302 or even a 350 may give you breathing problems at higher rpms. I'm not as well versed in the intricacies of TPI as BLK MGK and others, but from experience, I know it works well!

 

Believe it or not, Lingenfelter may not be ultimate word in TPI performance(eventho he's doing some great work for GM). Myron Cottrell, who owns TPIS out of Minnesota((952)448-5330), developed the TPIS mini-ram in the early 90s. Hot Rod mag(I believe) did a series of HP tests in 92 or 93 using 383s. All the engines were the same cept for the intakes. one had a stock TPI manifold. One had a larger TPI manifold with siamese runners. One had a big Holley 4 pot. One was a Lingenfelter setup, and the last engine was equiped with Cottrell's TPIS mini-ram. To make this story short, the TPIS setup edged out the Ling setup both in broad power and top end HP. The other setups didn't come close in HP but did make more torq at lower rpm.

 

Jegs(and I'm sure Summit et.al.)sells Cottrell's TPIS catalog and info book, and another book called something like 'TPI Insider Tips'. The Hot Rod Mag tests are in the TPIS catalog and info book. Hope this helps! (If you wanna go in this direction)