ok, so my buddy and i are putting a tpi system on his lt1 cammed 305 that we put together for his berlinetta. it's currently got a holley on top with a non-cc hei dizzy in it. the body harness is untouched, but the computer is gone. car was originally a carbed lg4, so it had a mechanical pump...we'll be needing to figure out how to wire in the electric fuel pump.

now, we have access to a complete tpi setup from a 1987 gta with the l98. this is all the hardware, sensors, injectors, full harness and computer. i also have a set of tpi fuel lines to run under the car. i also have a 1987 camaro sportcoupe that was originally a v6 car that has a good body harness. only thing i know that i don't have is a fuel pickup and fuel pump. we'll have to locate that.

the berlinetta has the digital dash and it's not an option to swap it out. we have to keep it. along with all the stupid little digital push-botton things too.

given all that i said, can anyone steer us in the right direction on this swap? i'm completely clueless when it comes to the TPI systems.

 

Well I am not an expert here either but I would assume that the digital gages use the same signal input that the analog gages did on all other f-bodies. Hopefully someone more knowledgable than me steps in but I think I would put the complete GTA harness in the Berlie and go that route. I am assuming you are running an automatic trans and AC and all that. You will need the torque converter to unlock properly and all that jazz, so again I would make an educated guess that the GTA harness and brain would go into the berlie and run the digital gages just fine. Swapping the whole harness will require some work, but it would be the least amount of cutting and such. Then if the car ever acts up you can just plug a scanner into the ALDL port and treat the car as if it were the GTA the harness came out of, much easier to diagnose that way.

That was all a total guess though, hopefully someone on here knows for sure if that is true.

 

sorry, let me re-state that. i have access to the full TPI harness, not the GTA's chassis harness.

 

so, anyone have experience with swapping a TPI system into a pre-85 carbed car?

 

You'll need the ECM, the harness from the ECM to the engine, the firewall-mounted relay center from the donor including the ESC module, and a fuel line set.

AFAIK, the digital instrument cluster is different than everything else. I'm not sure how it will interface. Homework time.

 

Man, thats a tough one. Maybe it might be a hell of a lot easier to do a custom dash with some Autometer gauges. Just my

 

I would suggest that your friend picks up a Helms manual for his 84. When you drop in the TPI harness, you may need to rewire/repin certain circuits to line up with the C100 bulkhead connector on the driver side firewall, and the C207 IP connector behind the dash.

I don't see any reason why your digital gauges would pose a problem so long as the dash wiring has been untouched. It would just be a matter of lining up inputs on the C207 and C100 connectors.

Personally, I would not modify the dash wiring under any circumstances, I would make all necessary changes to the TPI harness itself.

 

i agree, and we don't plan to touch the under dash harness if at all possible. now, the c207 connector, is that the one that goes from the ecm to the underdash harness?

 

well once it stops raining i will go out and look at my 84 berlinetta with the digital gauges... for some reason i think the guages feed into the computer.... the whole harness for them when that way. i think the only thing that did not was the speedo. which was a normal setup (mechanical with digital read out.)
I have heard that those dashes are rare anymore in working order. so i would keep it.. probably make the reale of that thing more one day if it ever gets sold.

But yea.. i would get a manual on it.. I know the haynes one is useless wit that one, as i do not see the wiring diagram for the digital dash in it. so you may want to make sure it has what you need in it before you purchase.. Not many of those digital dash optioned cars were made lol (compared to the rest in each respective model)

 

the speedo is infact digital with an electric sender. the guages are all independent from the computer as we nolonger have the computer in the car.

 

If the instruments are working, and you no longer have an ECM connected, you probably answered your own question. If that is the case, and evidently it is, the IP likely uses the "regular" analog inputs from the sensor array and digitizes it for display locally (without external electronics support). That being the case, there should be no IP trouble as a result of the swap.

 

yeah, i realized that after i posted...so, there is a connector that goes into the ecm coming from the underdash harness. what is that for? is this were the ecm gets power?

still wondering how i'm going to wire the fuel pump...

this is going to be a neat finished product, a 1984 berlinetta with IROC suspension, Walter Racecraft STB, SFC, Wonderbar, LCA's, Panhard Rod, and an lt1 cammed lb9...gonna try to talk my buddy into a 5speed swap, though it will likely get a slightly beefed 700r4 w/ mild stall, 3.42 gears. weighing in right around 3200lbs w/o driver

 

hey matt the only thing that you might have to do is use the senders from the set up now so the gauges work right. like temp and oil pressure. but the rest shouldnt be that bad, just hooking the two togeather or getting the tpi to stand alone

 

sean, when we go to do this swap, i think we may need your help. it'll be a little while yet, though.

 

i dont mind that at all matt. i will do what i can do

 

so? how did it go? I am looking to swap a TPI motor into my 66 while i rebuild the stock 400 and I'm having a tough go finding carbed=>TPI resources.

 

EvoTech1, if its not going to be permanent you may want to go with the under hood ECM, i think its the 727. by putting the ECM under the hood you won't need to cut a hole for the wiring harness in your firewall.
if you make the harness a stand alone type setup it shouldn't be too big of a deal. a few grounds under the hood, a power supply thats always hot, & a switched power supply is about all you need.
as far as the harness part goes, the VSS will probably be the hardest part of it, you will probably need a sensor you can mount on the trans where the speedo cable goes & then hook your speedo cable to the sensor. without a speed input you will probably have some intermittent stalling when coming to a stop.

the fuel system will probably take the most time to get worked out. you will need a return line fitting added to your sending unit & then put a return line on the car. on the fuel pump, a high pressure inline pump would be the easiest way to go, you may need to put in a supply pump back near the gas tank as most high pressure fuel pump can't pull fuel from the tank very good.

 

i've done this swap on my 86 ccc car, the ecm connectors connect to an under dash harness this is where the ecm gets power the fuel injector power, tcc for auto transmission, aldl diagnostic port, and i think the older tpi stuff it has the fuel pump wire, out side of wiring this connector up it's cake, except for the fuel system