ok. call me stupid but i'm really thinking of doing a tuned port conversion. i have a 91 formula with a 305 tpi. i have a guy who will sell me a complete tpi 350 for super cheap. so, the wiring and comp are my biggest problem. will an 85 vette harness and comp bolt right up? and will my digi-dash still work? thanks guys.

call me stupid.... i have a 91 formula with a 305 tpi..

You want to put the '85 350 in your '91?

You have a complete TPI setup now; why wouldn't you use what you already have that workss
Harness / ECM/ sensors /etc and get the computer chip retuned to suit the 350.All you change is the engine ; not ave to rewire whole car
(85 chip won't work in 91 ecm )
'85 ECM is not the best if you have better options

Sorry. That didn't sound right. I meant I wanted to put tuned port in the 84. I was thinking of using the manifold and stuff off the 91 to put in the vette. The engine they put in my 91 has perimeter bolt heads on it. So it would work on the 84s heads. I'm just trying to see if the 85 vettes harness will fit in my 84.

anybody got the answer to this?:givemebeer.sml:

I wanted to put tuned port in the 84. I was thinking of using the manifold and stuff off the 91 to put in the vette. So it would work on the 84s heads. I'm just trying to see if the 85 vettes harness will fit in my 84.

Confused
If you can buy a complete TPI 350 why do you need parts from the '91?
You can make anything fit .would need all the 85 engine wiring and computer.Also need a MAF because ' 91 was speed density

It is possible to tie in a harness from a tpi into the 84 but a very major undertaking that will leave you chasing little things for ever. It might be better to just sell the 84 and get a later one. I did the change once years ago and it took me over a year to get it all right. You almost have to change the tranny to an 86 up to get the torque curve right as well. The 84-85 auto had a smaller pump and different valve settings in it... i am not a tranny person so i could be wrong on specifics...just found out there is difference after i was done.

Confused
If you can buy a complete TPI 350 why do you need parts from the '91?
You can make anything fit .would need all the 85 engine wiring and computer.Also need a MAF because ' 91 was speed density

The current engine in the formula is a 305. The Vette is already a 350. So I was going to put the 350 tpi in the formula, get rid of the 305, and use the leftover induction parts on the Vette. Then I'd only need the harness and comp. Just not sure how hard it'd be to integrate the 85 harness to the 84.

The current engine in the formula is a 305. The Vette is already a 350. So I was going to put the 350 tpi in the formula, get rid of the 305, and use the leftover induction parts on the Vette. Then I'd only need the harness and comp. Just not sure how hard it'd be to integrate the 85 harness to the 84.

So the actual question is ,
"how hard is it to convert a '84 crossfire to TPI ?"

You will need a new hi pressure fuel pump and all the TPI electronics.The hookup to the dash is probably the same but you are going to be doing some rewiring.Would be easier to get the '85 internal under dash harness as well then everything would match up as you need the '85 computer.
Actually it would be easier to use '86-'89 system; better computer cheaper parts and less complcated.
'85 has 1 year only burnoff module ( expensive) whereas later have relays.

Read
http://www.corvetteactioncenter.com/forums/crossfire-injection-mine/54560-84-crossfire-tpi-conversion.html

http://www.camaros.net/forums/showthread.php?t=62122

http://www.digitalcorvettes.com/forums/showthread.php?t=64387&highlight=crossfire+sy1