firebirdpower7

hi, i have 91 firebird with a 305 with tbi. i want to put a tpi on iti found a good one on ebay that came out of a 87 iroc with everything even the computer and wiring harness heres the link http://cgi.ebay.com/ebaymotors/tuned...892QQptZMotorshttp://cgi.ebay.com/ebaymotors/tuned-port-injection-_W0QQcmdZViewItemQQhashZitem19c70de0c4QQitemZ110713757892QQptzMotors im wondering if their is anything i need to consider when doing this, any potential complications, or is t just a simple bolt on job. any help or hints you guys could give me would be very much appreciated

G-reg

iTrader: (3)

Its going to be a pain in the butt to make that setup work on a '91. You'd still have to buy more parts than what is listed in that auction too, you'll need a new fuel pump (TBI pump doesn't have enough fuel pressure) and also new feed and return fuel lines to go from the hard lines to the fuel rail. I don't see a MAF sensor or the air intake tube either. Don't forget about intake gaskets too. I don't think you'll even be able to use that computer or wiring harness. The older cars had a cable driven speedo, yours is electric. No provisions for the airbag wiring either. Throttle cable is different and not included in that auction. That wiring harness is also for a camaro and you have a firebird, so all the wiring for the battery is going to be too short (camaro battery is on the passenger side) and any charcoal canister wiring is going to be way too long (camaro has that on the driver side). There's probably a lot more that I can't think of at the moment too.

If you want to swap to TPI, the "easiest" way is to get the TPI setup out of a 1990-1992 car with the speed density. There's a sticky in the TPI forum called "how to repin TBI to TPI" so you can use your existing wiring harness, you just need to put different ends on it so it can plug into the '7730 computer and add injector plugs, its really not bad at all. The rest of it is removing and replacing parts, not too difficult just time consuming.

Mongoose

iTrader: (2)

I agree with everything the previous poster stated about the swap with exception to the fuel lines. The feed line will have to be changed but the return line should be ok (I reused mine and have had no issues in 5 years) or you can use braided SS lines with the AN adapter fittings like I did after the swap was completed. I should have a spare set of the OE lines somewhere if you're interested.

firebirdpower7

would it be possible for me to use the computer and wiring from that to just run the tpi and keep my old computer and wiring to run everything else? or would this be just as much trouble

Mongoose

iTrader: (2)

Wouldn't be worth it even if it were possible. Plus the TPI computer is a better ECM than the TBI unit.

firebirdpower7

ya thats what i thought but figured i'd ask anyway. ok well i guess i'll have to keep looking for the rite one. thanks help guys, you saved me alot of trouble

Mongoose

iTrader: (2)

You didn't mention this in your opening post but if your car is a 5 speed I believe GM still offers the needed harness for the manual cars through the dealers. I've been considering buying one and having TPIParts.com convert it to auto but haven't got around to it.

firebirdpower7

well at the moment its an auto but i plan to put in a 5spd some time soon, probably rite after i do the tpi swap or i mite do it the other way around idk