Sorry, I read the "Smog Laws" thread and got lost in legal jargon . . .

The 305 in my 86 Z28 went from a slight miss to a dead cylinder in the course of about 2 days, so now the thing barely runs. The thing is, how much money do you really want to spend to fix a motor that makes, on a good day, 160-something horsepower? So, since this is a father/son project and father is footing the bill , we're talking about just going to GM and getting a crate small block that makes a couple hundred horspower and has a warranty.

My question is this, to those who have dealt with GM direct crate motors, how clean do these things burn straight from the factory? Can I get it smogged (CA) just by leaning it out a tad before the test or is it going to involve more than that? Do they run clean enough from GM with all the stock smog equipment that I don't even have to worry about it?

 

I knew a guy from Sacramento through work who did the same thing - they used the 290 horse crate. They didn't have any problems getting it through smog, just transferred all of the equipment off of the 305. The computer controlled carb does just fine with a 350 under it.

I passed the dyno sniffer easily in Colorado with a souped up 305 (haven't had to test the 350 - have 5-year "collector" plates on it now, no emissions test required as long as the plates don't expire). Only problem California would cause with my combo is the headers are for TPI, not carb. If you want to do headers (not a bad idea, since the LG4 exhaust chokes a 305), go with the L69 (HO) application parts. Edelbrock TES is the only one available I know of, that's the only issue. Oh, and you'd need to do complete L69 exhaust for it to work best.

Just be sure the miss isn't being caused by something that would be transferred to the 350 - like spark plug wire, distributor cap, etc. Of course, I would consider replacing all of those things a "must do" with the new engine, anyway. But, maybe that's all you're looking at to get the 305 running right as it is (unless you're really looking for an excuse to put a 350 in).

 

I doubt the miss was caused by anything like a plug wire, as it now has absolutely zero compression in that cylinder. It's most likely a valve that's stuck open or something.

The motor we're actually looking at is the ZZ383, does anyone know if GM has published anything that would clue me to how that particular motor would perform in a smog test in comparison to the 290 horse crate Five7Kid mentioned?

 

Whoa, you're talking a real crate!

That's the 3.80" stroke shortblock/Hotcam with Fastburn heads on it. Fastburns use the Vortec intake pattern, which requires a Vortec intake manifold. The only Vortec intake available with EGR is the Performer, which will cause 2 problems: 1) You can be sure that 425 horses wasn't measured using a Performer intake manifold; and 2) you would have to plumb the EGR valve externally.

#2 is going to cause you problems with the visual inspection (assuming Herr Inspektor has any sort of a clue what he's doing - a pretty good bet), to say nothing of the aluminum heads raising questions. You might be able to get the sniffer happy, but you'll never get that far because the inspector is going to fail you on the visual (the ZZ383 is not even close to emissions-certified).

The factory at one time offered a "HO 350 Camaro Conversion Kit", which put a ZZ4 engine in a carb'd Camaro with an emissions certification sticker in it. However, as you might have guessed from the "one time" part, it is no longer available. Unless you find a dealer who had one in the back corner of their warehouse and forgot about it. That's about as much horsepower as was ever emissions certified.

Ever considered an LS1???

 

I'd thought about it, but since the car isn't fuel injected to being with, swapping in a fuel injected motor is more of a project than I'd rather get involved with. Also, I'm not sure we'd have enough time. We're trying to make the next event on November 18th.

Besides, carbed motors sound so much cooler =)

So the ZZ383 is out, I'll talk to the guy with the wallet and see what he wants to do. Sounds like the 350/290 is going to be our best bet for now.

 

What event is that?

My LS1/T56 receptor is original carb. Doesn't complicate it that much at all. Going auto to manual is the bigger deal.

 

Drift Day 39 - a little local drifting event here in So Cal.

I'm one of those new-fangled crazy kids who'd rather go around a turn sideways than straight.