Originally Posted by Chevyboy_0
So I found out that Painless Performance has harness for My setup, this is a quote from an email I receieved
"Hello; we do offer a stand engine management harness that will allow you to
operate the 5.7L Vortec in your Chevelle #60212. this harness uses a factory
computer #16229684 and does not need to be reprogrammed"
Has anyone installed a Vortec Truck motor in to an older car. also Can I reuse my TH350 tranny or do I have to use a 4L60E/4L65E?
You are standing on the edge of a complex swap. Not to mention expensive, you'd better get a quote on that Painless bundle, that will be your first painful experience.
The least complex and onerous way to do an EFI swap into an older car or truck is to go to the wrecking yeard and make a deal for most all you need from a doner vehicle.
For a full up vortec the only source is Chevy or GMC trucks. Be aware that if you have to smog in a state that uses California standards such a swap makes your 70 Chevelle subject to the new engine's emission requirements.
Even if you don't have that requirement, you've still got a lot to do. First off is whether to take the modern transmission. They have sensors and resolvers that supply the computer with information. Part of your problem will be that they only supply information for a mechanical speedometer, so if your keeping the original, a digital to analog converter has to be put in the system that converts digital input into a rotary output to drive the speedo. The other way to go is to keep the TH350, then you have to convert mechanical transmission data into digital data for the computer. There are people who trick the computer but these things are always never quite right.
Then there is the need for a high pressure fuel pump. This is electric and can be intake or externally mounted, either is a bit of work.
Then the Vortec injection isn't all that great nor is the engine configuration, if youre looking for power you've got to make substantial hot rod changes to the cam, and compression. Plus Vortec injection is next to useless for performance work and needs a lot of redoing to get rid of the troublesome Vortec pop off injectors with TPI style injectors.
All in all this is a coplicated and pricey swap, don't let anybody kid you about how easy and cheap it is. Without the 4L60E transmission, this cannot be justified at all, it is the key to better mileage but these very high cruise ratios really require injection in a heavy vehicle.
But cost benefit basis it isn't there, you can drive a long time at current gas prices for what this swap will cost in the end. I do a lot of S-10/15 Vortec swaps and I would say using a decent stock L-31 and 4L60E that don't require rebuilding, all the junkyard wire bundles, high pressure pump and fuel tank equipments. To make one of these in an emissions legal environment using mostly junk yard parts ranges around 3000 dollars for parts and that's real basic.