I found a complete and used zz4 going for $2200 with 25K miles. I talked to the guy and he said the heads were milled down a little and the cam is a little bit bigger, I didn't ask for specs. Is there anything you guys can thing of that would prohibit this engine from potentially passing a california smog inspection, given that I throw all the egr stuff on it of course?

Also how should I inspect it, since it's still running. I figured a compression check is in order but anything else?

Thanks

 

If you're talking about putting this in your 91 Z28, then yes, the ZZ4 itself might pass.

The EGR won't actually "work", because the passage for it doesn't exist in those heads. I don't know offhand if your year has the "heat sensor" thing on the EGR valve; if it does, then it won't pass because it won't see any heat. On the other hand, if it doesn't have that, then it probably will.

This is assuming of course that you put a cam in it that is compatible with TPI and emissions. I obviously have no way of knowing whether whatever whoever put in it, is such a one or not. I'd suggest either getting a take-out ZZ4 cam off eBay or some such; or, for a little boost over stock, use a Comp 502 grind.

The ZZ4, with a stock TPI cam on it, puts out essentially identical power to your L98. We know this, because part number for part number, it's the same long block as a Vette L98. So don't expect any kind of radical performance difference. If you're just looking for a motor because yours is dead or something, though, it could possiby work out great.

 

Well, the ZZ4 cam is a good step up from the L98 cam.

 

I used a ZZ4 camshaft and heads on my previous engine. You'll need an aftermarket TPI intake that has the Corvette-style EGR on it. You'll need a set of Dyno Don's headers (search the exhaust board and PM him for details) with the EGR setup on the #8 port. And you'll need to get an EGR tube from either Scoggin Dickey or the junkyard to make the connection between the #8 header port and the EGR port on the intake manifold. Lastly you'll need to contact me to get a custom chip burned to make it all work.

It made 282 RWHP and 380 RWTQ thru long tube runners and a T5. It also ran 13.23 @ 107.19.

Edit: Here is the thread with the pics of my old headers:
https://www.thirdgen.org/forums/tpi/...emissions.html

 

Thanks for the help guys. I probably will end up contacting Kevin if I go through with this.