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Poolplayer 01-23-2013 03:45 PM

Transplanting a 85 Corvette 350/700R4
I have a running 85 corvette that was in a slight rollover. The car runs and drives but the right side roof is caved in, glass is broken, and has been open to the elements.

So, I want to transplant the engine/transmission to a 65 chevy pickup. I can read schematics somewhat and do fair with 12V systems.

1) How hard is it to move all the modules and wire the motor and trans.

2) I know that the motor is only about 235hp but wanting it for a daily driver.

3) What is the cheapest way to wire the engine/trans...reuse the existing wiring harness or bite the bullet and get a painless or generic harness to do the job.

4).... or do you recommend to reuse the 400/th350 currently in there because of easier than wiring in the 1985 setup.

Thank you in advance

EOD Guy 01-23-2013 04:00 PM

GM performance parts sells a trans and engine computer that was made for exactly for what you want to do. It is possible to clone the old computer into doing what you want but there is some re-programming involved for the ECM to work without the VATS system etc...

kso 01-25-2013 10:39 AM

If you do the swap I would spring for a Painless or similar coversion harness, unless you really enjoy poring over diagrams and soldering wires (which you might...I don't know...). Integrating a factory harness is a days-long chore and involves aspects that can be simplified/eliminated in an older vehicle, which you can avoid by letting those suppliers do the work for you.

If you're keeping the engine stock, the factory computer/prom will work fine, there will be no VATS issues from an '80s system and the MAF (as opposed to speed-density) scheme will handle minor changes. All the modules etc. that look like such a mess in the Vette get a little easier to figure out when you've got them laid out on the living-room floor.

That said...first-year '85 TPIs are not the most desirable, '86-89 are a more sophisticated and reliable deal. TPI units in general appear to be losing favor, and GM seems to be discontinuing some support. Sweet as that motor looks, I might do more investigation before investing a lot into it.

My own TPI swap into a newer El Camino, integrating harnesses/retaining effective ESC and staying CA smog-legal, has been an on-again/off-again project for years and has yet to be completed thus I cannot say I'm the expert here.

75gmck25 01-26-2013 04:47 AM

If the Corvette is complete and you transplant everything in the engine compartment you probably won't use any engine wiring from the truck. There won't be much "integration" because you won't need wiring from the truck. This solution will work, but it will take time to move it all over correctly. One caveat - If the Corvette has antitheft (VATS) you will have to also use something to bypass it.

If you have the time to do the work, this transplant is probably worth it since you are only spending your time, and it sounds like you already have the Corvette. But if you need to buy a lot of parts to make the Corvette drivetrain work then there might be other alternatives to consider.


LATECH 01-26-2013 05:59 PM

I agree with GMC , use all the corvette stuff.
The vats will be easy to bypass. Just place a resistor the same value as the pellet on the key, hardwire it to the 2 wire orange harness under the column harness and you are done. Be sure to keep ALL the corvette harness as the VATS module may be a seperate module as some /most were.
Having the whole have evrything you need to do the job.
Buying an aftermarket harness /ecm etc is a waste of money.
Wished I lived closer, I would swing by and give you some very helpful pointers. The wiring /conversion you are doing is a blast, and easy.(at least for me it is :D )
I'll watch this post and help you out here . Way cool . :cool:

Poolplayer 01-26-2013 08:10 PM

I'm pretty experienced in restoring 60s Mopar's and I'm very nervous about doing this conversion. I don't know really anything about modern electronics etc. i don't know the names of any of the modules. I have no idea what they look like I'm worried about the connection through the firewall to the steering column, and instrument cluster. I really don't have any clue what I'm doing as far as building a "hot rod" This is my first one. In restoration the blueprint is already there in front of you all you have to do is clean it, Repair broken parts, and paint it. this is a whole other ballgame and I'm looking forward to the challenge. As I've said before "being hard is what makes it great" to borrow a line from league of their own. LA Tech I appreciate your offer and I'll probably take you up on it from time to time. I do plan on posting photos et cetera. In Texas we're about a month away from spring. I plan to start pulling the Motor/trans from the pick up and then start pulling the Corvette and Hardware apart! Open to any and all suggestions thank you

LATECH 01-27-2013 11:00 AM

First thing you want to do is aquire a wiring diagram for the powertrain .
Thats a must.
Also get a diagram of the electrical component locations. You need it to find all the modules that you will be running.Should only be 2 or 3 but non
theless you need to ID the ones in play. Should be PCM, VATS Mod and maybe BCM...or not.
Get both of those in Print, maybe laminate them so you keep them clean and you will have them for future reference.Or download a full set to a file on your shop PC. the connectors and how they come apart without destroying them. They are all pretty simple once you take a few minutes to understand how they work.Keep the tabs intact and keep the locks also.
Also learn how the fuel system lines are put together and do not cut
anything there as you will want to use some or most of that.
There is plastic fuel line available also to fab up lines to the truck and when you get to that point I have some pointers I can give you in that dept as well.

So dissasemble ,with care as you may or may not need anything from the vette.
You will also notice the fuel pump comes out of the tank pretty easy, and you may want to get started scoping out how you are going to run a in tank pump in the old 65. :cool:
Neet project!
I will be around. Please post any questions on the board, no PMs please, as any info posted will help other guys in the future, with a PM it only helps one.
If needed , PM me to get my attention to a specific post. No problem
LA Tech

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