I have an '86 iroc-z with the 305 HO carbed engine. I want 350hp or more but still remain emissions legal here in Ohio all they do is check the exhaust they dont check under the hood or anything. What do you guys recomend, most likely a 350 block but could I use a zz4 and swap over the emission units to it? Also it has a manual T-5 should I get it rebuilt or leave it alone or swap over to an automatic. Thanks

 

GMPP offers an emissions legal swap for carbed cars from 82-87, basically its just that, a ZZ4 block with a nice cam, better flowing heads, tuned computer, intank fuel pump(replacing the block mounted one), and a dual snorkel air cleaner. There are a lot of other little goodies, the kit is supposed to come with its own 3" high flowing exhaust with high flow manifolds and what not. But yeah, I am sure you can still get it to pass smog as long as everything goes back on. I would think a fresh motor would actually burn cleaner than a seasoned L69... Good luck., check out the GMPP website for more info

WIll

 

i think the one key part is how much money do you have to spend on this project

 

That's the key part of every project.

 

well i must say the manual v auto is really up to you. if its stick, id leave it stick. if its auto, id leave it auto. more work and money to spend when you could be getting motor work done as for emissions, i dont see why you couldnt use a zz4 motor, as long as you keep your egr lines and the rest of the emo stuff. under the hood emission stuff you need for visuals but it doesnt do all that much for the sniffer. a nice cat will pass you on that. if your aiming for 350 hp, it will be easier to do with the 350 but you can acheve it with a 305. you know, you could just leave the 305 and pop a blower on top and they will get you over 300 hp easy

 

How about the engines on Ebay? They are cheaper then the zz4 from Summit and advertise over 400hp for the complete engine that would be the same as the zz4 configuration wise wouldnt it? Id still be able to use the emmission stuff on it i would think. Are the advertised power on these engines on Ebay true or are they just saying it to sell them?Also what would I have to do with the t-5 for it to be able to hande the 350+ hp?

 

if you babied it would hold, one 3k clutch dump and youd frag the whole thing. The upgrade option would to either buy a used t-56 6 speed out of a 93-97 lt1 camaro or you can buy the same trannies new. Actually D&D performance sells modified viper t-56's to put in our cars for 2500.

 

Thats pretty accurate seein how he has a NON WC T-5...they were garbage....the WC design is a little tougher.

 

It is my understanding that the Kit is no longer available through GM, unless you can find someone who still has one on hand such as Scroggins-Dicky. The parts are serviced individually, but no longer sold as a kit. This info was posted in the '03 GMPP catalogue.

 

Good to know, I was unaware they stopped offering it like that. I had originally planned on doing this swap to my 86 LG4. Seems like the way to go for smog legal performance, But it had a nice price tag attached

Will