Hey, Listen, in the past i have owned an 86 Z28, traded up for a new 89 IROC back in the day...

Question is, that i am looking to rebuild an older IROC, ( 85-90) are any of the years less desireable than the others? Since 85 was the first year of the IROC and 90 was the last, are those considered more as a "Collector" with regard to these cars..?

Reason for my question,i am looking @ an 85.. a4, 305,.. no air,pw,ph, etc.. which is fine.. Tell me about the 85's?? I hear that some of them had a higher duration (revving) cam..? Is this accurate?Not that these cars are HP beasts.. I would simply like to have one, fix it up, and enjoy it as i did my old 3rd gen cars..

Any "constructive" input would be nice...

Thanks...

 

I'm trying to remember all this off the top of my head so you might want to check my facts against what a search here will turn up, but IIRC...

The 85 had the slowest computer of any TPI, '86's got a newer and better computer.

'87 is where you really start to find 350's and if you want an A4 there is no reason not to get a 350 (IMO).

'87 (I think) is also when they went to a roller cam and one piece rear main seal.

'91 they had dropped the IROC name but I like the styling changes for '91 and 92'.

In '89 they went to the PBR rear disks which are bigger and better than previous. The pre-89 rear disks leave a lot to be desired.

Some time between '87 and '91 (don't know which year) they went from a MAF based to a MAF-less computer. The MAF based ones are easier to mod as they will make a larger range of adjustment without reprogramming...but if you get it programmed properly the MAF-less is better and does not have the restriction of the MAF.

This is by no means a comprehensive list, just the first things that came to mind in no particular order.

 

IMO, I wouldn't buy anything older than a 1990. 1990-1992's are Speed Density which makes tuning for bigger motors / cams etc.. alot nicer.

Or consider a 1982. Then update the body to anything 85-92 and drop in a built carb'd big block and not have to worry about emissions!

 

I look at it like this when "special" comes to mind

1985 The first TPI F cars, means something to collectors and may mean comething in the future.

1986-VERRRRRY RARE were the TPI 350 cars, hard to find a original

87, yes, the first year of roller.

1990 was the nicer gauge set, last of the IROC badging

91 and 92-TONS of people like the wing, tail lights and GFX change. This is verry popular toi have changed on allot of peoples cars from 82-90. They are apealing GFX to so many.

I love the 85-90 because the tail lights and GFX look better to me, but that is me. I also dont know if you can get a 9 bolt posi in anything after 1989, i could be wrong.

90 is optimal to so many due to speed density, and you can still have a original IROC.


SOOO many different things to consider, go with what you like and swap the things in you want if originality is no concern.

 

I thought you could only get a 350 in 87 and up not in 86?

 

As i said, very rare, i have never seen one original, but yep, they did. Not the firebird though. It did not for sure till 87. Thos might be the rarest and most valuble in 15 years.
----------
I did forget to mention, the 92 B4C cars, i have seen 10 or so myself, those will be a good car to own in 15 years, less than 600 made, and the only RS to ever be able to get the TPI 350.

 

the 85 and 90 are the first and last year so they have some significance. It kind of depends on what you want to do. I preferred to get one that had a 350 in it, like stated above, over a 305, again . Really just find a clean one and start having FUN!!!!