I recently bought an 89 iroc convertible with no motor or trans I bought the correct motor for it from what I know (im new to TPI) the 89 had no 9th injector for cold start. Im lookin at my wiring harness and everything seems to be okay no 9th injector plug all seems fine and correct except for the distributor plugs ins. It has old style (large hei cap) connectors for the coil and ignition module the connectors seems original (not spliced in). From the research ive done my car should have connectors for the small cap style distributor and module. I looked at some wiring diagrams and from what I can tell all I have to do is change the ignition module connector and the coil connector since the wire colors are the same and seem to do the same thing. Will the computer control the injectors properly with the small cap distributor? I would like to know before I start cutting and splicing and would anyone happens to know why my wiring harness is this way (1989 correct injector wiring but old style large cap HEI distributor connectors 1985-1986)??

 

I think some of the Firebirds with TPI still had the coil in cap dist in 89. Maybe you have a Fbird harness?

Did the car come from the factory with TPI?
Some 89 IROCs were TBI.

Look for an 8 (L98) or an F (LB9) In 8th digit of VIN as these were the TPI engines.

If it is an E it was the TBI 305

 

I am pretty familiar with tbi and the vin E I was scared it was gonna be tbi but the vin does say F thank god lol so it probably is original because the wiring harness seems to have been re loomed at some point so some stuff isnt were it normally at compared to my brothers 88 iroc but it does look original nothing seems to be cut or spliced I just always thought all 87 and up cars had small cap distributors. So could I just convert to the small cap by changing the connector since I already have that distributor or will the car only run with the big cap one?

 

for your response

 

If you already have the dist with the seperate coil you could just swap the connectors.

If you still need the coil then you could just get the other style dist cap.

One very important thing to consider; 87-up roller cams use a different distributor gear. Make sure you have the approriate one for your application.

Good luck with your project!

 

:Sweet! good to know I have connectors distributor and the coil so it will be cheaper and easier to do the conversion instead of getting the old style one im excited to hear her run and thanks for the heads up on the cam . It is a roller type style distributor and the motor has a roller cam thanks for all the help I will post pics in a week or two