i am planning on swapping my 305 carb mtr out for a L98 into my 85 ta. my concern is wiring. i have a wiring harness out of another 85 ta, a L98 out of a formula and fuel lines and pump. am i going to have any other wiring problems besides the fuel pump. hoping for plug and play.

 

There is no "plug and play" with an '85 TPI ECM. It's among the worst choices for a donor. Perform a search of the TPI forum for swap ideas and tips. I just spent the last two days manually cleaning up the old messages, so the search should yeild a lot more meningful results.

 

my car is a 85 ta the donar car tpi harness is as well out of a 85 ta how much difference can there be. i got all relay's, sensors, fuel pump and fuel lines the only thing that is not from a 85 is the motor.

 

1985 was the first year TPI appeared in the Corvette and
our F-bodies

 

Although the 85 setup is not all that desirable due the ecm and mass air burnoff module, thats about all there is different compared to an 85-88 setup. You can reuse the 85 tpi harness you have. You will nee an 870 ecm with the mentioned module (mounts on top of the ecm).

 

i have the ecm took it a well when i removed it, but i don't remember seeing a module on the ecm. the donor car ran till tme of removal.

 

its a light baby blue chip inside the metal box.
I wish I had a pic .. I know someone does.

there should be 2 screws on one side of the box.
remove them and remove the PROM to replace it
with the one desired.

 

the tpi ecm i have is the one that was in the donor car, i removed everything from the donor car, so i looked inside and both modules are black does this mean anything? 1 is smaller than the other. my concern is there going to be any repinning or wiring troubles.

 

Your Plug and play solution-

If money is not the issue-

GO WITH A PAINLESS HARNESS.

- Gather the required sensors.
- Grab the right computer
- Obtain the right chip

You can route your aftermarket harness check engine light through to the factory provision.

It looks very nice and clean too.

Using a wiring schematic, strip out what parts of the harness you don't need (solenoids, etc).

Put in your fuel pump and connect your lines.

 

The ecm he has does not use a memcal like you are mentioning. It uses a small carrier similar to the TBI ecms. The larger of the two chips is the "computer chip". It should have a silver sticker with a 3 or four letter code on it.

I'm attaching a picture of the ecm and module that I was referring to. The module is the box that is sitting on top of the ecm in the pic.

 

Personally, I wouldn't call a painless harness a plug and play product. Its not specifically made for a thirdgen like his current harness is. He would have to keep some wiring off the 85, and mix that with the painless harness. Reason being is that painless only provides the engine management items. It doesn't include anything for the alternator, a/c, wipers, etc...

Theres nothing wrong with the 85 parts really. Its just that the 86-89 harness and ecm are preferred due to design reasons. Even if you wanted to go with an 86-89 setup, it would be rather easy with the 85 harness. Theres all the need info to convert from an 85 to an 86-89 setup on Mike Davis' site. It involves a differen ecm and memcal, and a few wiring alterations. Not alot of work.

 

that module was not on the car that donated the tpi system. i,m not going with a 86 - 89 i have a 85 set up no need to change now. i am no good at wiring so painless is out.

 

ahh, I apoligize.. I was unaware that the 85 f-body ecm differs
from later models.

either way, smart dudes always come in and lend
a big hand to get the right solution

 

True- He'd have to pull out the parts of the factory harness that he doesn't need- but it can be done. I've retrofitted harnesses for Vettes- with painless systems- and pulled the unneeded factory parts. Check twice- cut once.

I'm partial to the speed density systems. False air will drive a guy nuts. I prefer the large cap distributors over the ESC module small versions. I also like the fact the painless set up is stand alone.

But either way- welcome to the owner-modded car society. The more complex and one-off your ideas are... the more you should prepare- no EXPECT- to spend A LOT of time crossing the T's and dotting the I's.

Good luck and keep posting your progress.

 

Yes it can be done. The harness thats in my car is a modified L03 harness with no cut wires. I had a mangled 85 TPI harness which surprisingly enough had the injector, tps, and iac leads uncut. I removed them all the way back to the ecm connector, and replaced the injector, tps, and iac leads in the L03 harness with these. The result is an immaculate, single fan TPI speed density harness for free.

As far as the car not having the module, what is the service number on the ecm you have? I have read on this board (but never confirmed it myself) that the change from the 870 to the 165 did not come in 86, but actually late in the 85 production run. If thats true, its possible you have the harness and ecm everyone has been suggesting is better.

 

i have no clue as to which one it is cause the service # is gone.but i do know that module is not in the donor car i just don't want to get into the mess my son has with his camaro we still don't have that one running all wiring troubles. so am i going to have to do any wiring?? if so i'll sell the tpi system before i get into that again.

 

Wow...I'm trying to remember... I sold that car a year ago.

Well, it was the model used on multi-port V6/8 engines that is a direct replacement for 91-92 Multi-port engines with the speed density systems.

If you can find a painless wiring harness manual, then you can get the schematics for how to use EITHER the big cap or small cap distributor.

Hope that helps!

 

i am almost sure that i have the 165 ecm, so what i need to know is am i going to have any wiring troubles harness is out of a late production 85 ta and i am going to put it in another 85 ta w carb everything should match up cept for fuel pump a relay will fix that.. like i said i have every part related to tpi from the donor car