Tuned port 350 into 1975 Monza

[Strokercutlass]

Ok...so I'm pondering pulling the 262 out of the IMSA and dropping a 350 TPI motor out of a late 80's Camaro into it.....even in stock form it should more than double the HP of the original 262 v8.......I have the complete Camaro as a donor car. I know alot of people prefer the speed density system, but I'll most likely try to stick with the MAF style system, since I do have Hooker Supercomp conversion headers, full dual exhaust, and may go slightly larger on the cam....from my understanding, the MAF system will learn easier than the speed density system, although it may be slightly harder to set up due to ducting of the MAF.....

Anyways, I know I'll need the complete engine assembly,ECM, fuel pump, lines, oxygen sensor added into one of the headers (unsure if which side matters or not, and how far down the header) Wondering about the VSS...this is a 4 speed car, so is there some type of conversion VSS that can be used in the Saginaw trans? Going to go with an aftermarket TPI harness rather than trying to sort out the original harness mess.....

Anything else I'm forgetting or should know before I start tearing in? Any recommendations for a good TPI cam?

[spencerforhire]

5-speed TPI F-body computers did not use any VSS signal input. As long as you're not using the PCM from an automatic you're ok. I'm putting a TPI 305 and T-5 from an 89 Trans Am GTA into my 77 Vega wagon; planning on using the stock MAF computer and harness. My only upgrades will be an ADS chip, a set of Hooker 2135's and some kind of cold air intake. Luckily the GTA used a remote mounted MAF meter and canister filter that can go pretty well anywhere; the Z/28 air intake tract and MAF would never fit under the hood of a Vega.

[ichevyguy66i]

One of my friends just did a TPI swap into a monza and had E-K Racing help him they should be able to tell you about any problems you might run into.....It looks to be a low dollar budget swap but they should have alot of info to share.

http://www.facebook.com/#!/pages/EK-Rac ... 2037294423

[TimMcCabe]

You need the VSS signal regardless of AT or MT ECM being used. If you han find an early '80's GM with cruise control, you can get the speed sensor off the speedo cable (fits inline with the original speedo cable). JTR (Jags that run) also make a number of speed sensors for TPI conversion.

Also, the TPI is not a high reving engine, so I'd look into getting an overdrive transmission(T5 works great, T56 works even better, I've run both in my Vega).

Good luck,
Tim

[Strokercutlass]

Somewhat slight change of plans.....drug an '86 IROC home yesterday with a 350TPI engine....good runner, same principle.

Not so worried about high RPM...I know the TPI is done around 4500 rpms, but this car, with the stock 4 speed and stock gearing, seems pretty decent RPM wise. I plan on pulling the complete engine, cleaning up and re-gasketing it, and installing it complete.....the only 2 main issues I'm coming up with other than adding a return line to the tank OR using the current line as a return and adding a new 3/8" main line, is figuring where in the header to add the O2 sensor, and the VSS issue. I thought about pulling the whole harness and cutting out what I don't need, but for $300 it might be easier to buy a swap harness and be done with it.

Should better than double the HP of the current dismal 262, have better throttle response, and be fuel injected to boot.....The fuel pump in the tank shouldn't be a big issue, since the Monza runs an in tank pump anyways...just jumping up to the TPI pump. Also, no power steering to worry about, since mine is a power brake, manual steering, no A/C car.....

[spencerforhire]

Tim(expert in all things speedometer related) is correct in that the TPI computer has a VSS input which it uses to control the automatic transmission, but I don't think it actually does much in one with a 5-speed(other than cause a "code 24" VSS fault. They both get their signal off the back of the instrument cluster speedo which is cable driven.

[Fastmax32168]

If you can use a VSS from a 700R4, then you can buy one for a 91 caprice police car and it supplies both cable and electronic outputs.
Otherwise there are some inline VSS output units available where the cable goes in one side and back out the other and the unit supplies the electronic signal.
Roy

[TimMcCabe]

The VSS is used for evap purge, EGR function as well as by the Idle speed contoller to prevent stalling during quick stops..
In my case I'm also using it for my cruise control as well as my electronic speedometer

Tim

[Monza Harry]

Re: your 262, 3 Years ago at the Frankenmuth MI car show, GMPP was there, and I was talking to one there guy's and he had mentioned that GM had 1 of every engine they ever made, except our little 262, they maybe still interasted in buying one. Good luck on both endevours, it would be nice to be remembered by the Mother Ship they haven't acknowleged H-bodies in forever.