IROCThree8Three

Girlfriends 84 Corvette has a 350 Crossfire Injection engine and wants to buy my TPI system off my 86 IROC Camaro. I'm pretty sure everything will match up, my only concern was the 4+3 Transmission. Will we have to find a new ECM since hers is a stick and mines an auto?

Jim85IROC

iTrader: (2)

The transmission has nothing to do with the TPI. All the TPI computer did was control the torque converter lockup, so it won't even notice that it's not there. It would be advisable to have a custom PROM burned, with your best bet being to start with the 86 TPI Vette 4+3 baseline.

nsimmons

The overdrive is ecm controlled. Your going to need an 86 vette
4+3 wiring harness, and an 86 vette ecm, as well as an 86 vette 4+3 shifter with the button on the shifter, you cant use the old switch. the tpi system itself will work fine, but the the electronics wont.

swapping to a stock tpi is a huge hassle for little gain, unless the crossfire is seriously wrecked beyond repair, its worth keeping it.

check this out.

http://www.crossfire.webhop.net/cftest

Jim85IROC

iTrader: (2)

Looks like I'm eating crow.

I forgot all about the OD control.

BTW, the Vette uses the same 165 ECM as the f-body, but I do agree that you'd either need the Vette harness, or make the necessary modifications to an f-body harness.

IROCThree8Three

Ok so if i'm hearing right i need to get a wiring harness off an 86 Vette with 4+3 tranny. What are the major differences in the wiring harnesses?

And why wont the overdrive switch in the 84 Vette work?

Just a bit confused but making progress Thanks guys

HatchetJack

Hood air ducts are different---should get 85 or up hood as well---

nsimmons

yeah i forgot about the hood..

you cant use the 84's wiring harness because it wont plug into the 86 ecm, you need a new od switch because the 84 is an on off switch, the 86 requires a mommentary contact switch, you have to request to leave OD mode.

Its gonna be alot of work work a 4+3 car, and auto would be easier, but still a pain in the ***, especially considering you need a new hood now..they arent cheap.

btw you need a new hood because the maf ducting wont clear the 84 hood, you could use a 90-92 speed density setup, but then the range and milage on the dash wont work as the Speed density setup and digi dash never came in the same car. I dont know if the 7727 ecm outputs the correct 5 byte data stream for the older dash, the new dash does have a milage readout, but i dont know if its the same.

oh yeah also you'll loose the mpg readout on the dash, and the camaro ecm doesnt output the proper data, now since the 86 camaro and vette ecm are the same it stands to reason that the code to output the correct data is on the vette eprom, but im not sure.

Your gonna be looking at the better part of 1200-1500 dollars to get it done, and its more than likely gonna be a botch job.

And thats just for all the extra equipment you'll need let alone the injection. At that point it'd be better to go with a super ram or miniram to justify the cost and effort.

Your best bet would be to modify the stock system if she wants more power, 325+ power is simple to achieve, if you need more than that a carb would be the easiest choice, if she doesnt want to spray it.

IROCThree8Three

Ok so its gonna be to much of a pain to switch intakes on her car, so what do i do with this TPI unit that i've put at least $500 into with injectors, afpr, new harness, and basically rebuilding it (Not to mention new TPI cam and lifters with less than 3000 miles on them?? Its to small to do any good on my 383 without completely porting it out and getting my prom reprogramed (which i cant find anyone who knows how to do it). I could sell it on ebay, but i probably wont get anything near what i put into it. So did i basically just screw myself over? lol

And how could we get up to 325 hp out of her car? It came from the factory with 205 and shes put straight pipes on it, but thats it. Only reason i ask is because she only ran a 15.25 at 94mph down at Beaver Springs and shes p*ssed. I figured i'd be a nice guy and sell her my unit with new SVO injectors and everything for cheap, but i guess not!

Thanks again
Seth

nsimmons

sell the tpi setup on ebay

Then visit the crossfire forum.
http://www.crossfire.webhop.net/cftest

A simple list for a 300+hp car.
Port the stock intake, grind the crap out of it, or get an xram manifold. www.x-ram.com It works good but its pricey, and I dont really consider it necessary for a 300hp car.

Nice set of heads, trick flows, edelbrocks, afr's but there really pricey.

Cam shaft, 210 duration, 480-500 lift, depending on the heads.

Bore the throttle bodies to 2"s 65 bucks Dan plett on the crossfire forum does a great job.

Set of headers, and exhaust, since she already has the straight pipes you can forget about mufflers.

Depending on the combo of parts, ecm tuning will be necessary for max power, but not entirely necessary, it will run fine, not great.

My mods are
Ported intake,K&N, MSD, Ram Air, 8mm MSD Wires, 85 TPI Pump, ADS B Chip

The intake mod was extremley effective, and it runs mid 14's at 96-97mph.

Im planning on some experimental intake work, new cam ported heads, and headers in a month or 2, im collecting parts still, and estimating 260-270hp and high 13's

Total cost about 700 bucks, and that as much as im willing to spend.