so im looking at picking up an IROC-Z been on CL a lot and cant find one thats a 5 speed hardtop in decent condition. i have seen a couple of 5.7 IROC-Z's in great condition but i live in CA so im pretty sure that they are all automatic. my question is; why is it that there were no 5.7 IROC-Z's made with a 5 speed transmission in CA? am i right to believe that it is due to CA smog laws? and if so; if i were to purchase an automatic 5.7 and had the tranny swapped, professionally of course, would i be able to have the vehicle legally smogged? or does the tranny have nothing to due with smog at all? any help would be greatly aprreciated!!

thanks.

 

None anywhere.

JamesC

 

There were no 5.7 5-spd combos made and sold to the public ANYWHERE, period.

Yes the trans is intimately involved in smog; while you see people claiming that the reason that combo wasn't offered was warranty problems, there's also a good possibility that they didn't want to spend the money getting it certified, or maybe even, couldn't get rid of the puff of hydrocarbons from letting off the throttle in between gears. In any case that's a can of worms you don't want to open.

However:

If you get a 305/5-spd car, you can swap a 350 in there; and as long as you keep it sufficiently stock to the eye - all emissions devices connected and such as that - I'd bet money they'd never tell it was a 350. Then if it blew clean on the rollers you'd be good to go, no awkward questions asked, no referree.

Incidentally, a number of people with absolutely no knowledge of California law will no doubt pop in here and tell me I'm full of crap, as always; and then there'll be a whole bunch of California bashing and name-calling, none of which is of the slightest value to anyone. Ignore all that and stick with the truth even if some of em tell you what you want to hear instead of telling you the truth.

 

that sounds doable and like it would cost just as much as the trans swap. what would i need to do to ensure it would blow clean out of the tailpipes? i mean, besides keeping the emissions equipment stock? or is it just an install and pray kind of thing?

 

o yea and thanks guys appreciate the info and help.

 

TPI itself is absolutely identical in every way between 305 and 350. Same TB, runners, base, etc. If you get a 305/5-spd car, just unbolt all that and stick it on the appropriate 350. Only differences are injectors, chip, knock sensor, and ESC module in some years. Shouldn't be too tough to get it to run clean if you get the correct those trim items.

 

Ok. So i think i found the perfect car to preform this operation on. Just one question, and i know this particular question belongs in a different forum. However, you seem to be highly knowledgable on the subject. And i do appreciate all your help. So my quedtion is; is the 350 L89 base the only engine that can be used for the swap? Or are there other GM SB 350 Tpi engines that would work?
Thanks again

 

Virtually ANY 350 could be used. Some would be ALOT worse than others.

There are no other TPI 350s from the factory besides the L98.