How to Swap a 1985-1992 GM TPI-EFI into a 1970-81 Camaro

This guide is designed specifically to swap a 1985-1992 GM TPI EFI system/engine into a 1970-81 Camaro. Though, for the most part, it can be used to swap in a TBI or LT1/LT4 engine/EFI system as well. All three engines install like a conventional engine on the existing motor mounts and they have the same transmission bell housing flange. The newest LS1/LS6 is a completely different animal altogether requiring extensive chassis modifications to install and will not be covered in this article.
The first thing you need to take stock of is your vehicle and the system you will be installing. You need to also consider the emissions regulations in your state and how you will meet those requirements. I’ll touch on the emissions system briefly, telling how to hook it up. The emissions control systems are not essential to engine operation (save for maybe PCV and canister purge), but again, the emissions regulations will dictate their necessity from a legal standpoint. In California, there is a rolling 30 year exemption meaning that currently 1973 and older cars are exempt from smog. As such, I am not using EGR, AIR injection, or any of the other late model smog devices. However, I did retain my 1971 charcoal canister purge and PCV system.
This article will cover two possible scenarios. The first is that you have bought an entire engine/transmission assembly or just the engine. You may or may not have the factory wiring harness and computer, you may or may not all of the sensors, injectors, and relays, or have bought new sensors to replace old or damaged ones. In this scenario, you have already taken out your old engine and or transmission and installed the new one in its place. You now need to reconfigure the rest of the vehicle to run the new power plant. If you are installing an LT1, this is your only scenario since the intake manifold cannot be bolted on to an older small block without extensive modifications. However, if you’re bent on doing something like that, visit the www.thirdgen.org site and do a search. Several people have adapted LT1 manifolds to work the TPI. I will touch briefly on the installation of a TH700R4 and how to adapt it in to a 2nd gen since this is what I did. However, I will not discuss converting to a later model stick shift since I have no experience in that area.

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