C3Vettesrock

When installing your zz4, did you encounter any problems. Do I need to do anything to meet emissions for inspection. Do the exhaust manifolds fit right? Will Hooker Header/Side Pipes fit easy...any help would be most appreciated before i purchase

Cruzmeisters

From literature from Jim Pace Performance Parts (www.paceparts.com), 2nd page dated 3/27/99, last sentence states "The ZZ4 is not intended for marine use, and should only be used in 1973 and earlier pre-emissions street vehicles or any year off road vehicle". :confused:
Cruz

bryan78nCO

C3VettesRock,
I have a ZZ4 in my 78 and it passed emissions without any problem here in Colorado. I had to put a smog pump on it all the S**t that comes with it and it passed with flying colors. Oh...and a cat. converter also. :cry
I am curious about the headers also. I would like to install headers, but it looks kind of tight in there. I think it was Jim Pace Performance Parts that has headers specifically designed for the ZZ4 motor and they say they will fit on a 78. :D
Hope this helps.

81vette

Do you have the numbers for your emissions test with the ZZ4? Which emissions test was this?

bryan78nCO

I'm not sure exactally which emission test it was, just the standard for CO. But I do remember that the allowable we somthing like 120 and it passed with a 40. I don't have the specifics in front of me, but it didn't have a problem. Of course, I had to forfeit some HP with all the emission s**t though. :mad
I will be able to get my collector plates in January and no more emissions will be requried here. :D I'm going to love that. Then I can tear all of that S**t out of there and get my HP back. :blueangel:

theandies

Jim Pace does have these headers and I installed them on my 71 with a 4 speed. The thing about the ZZ4 heads is they had "D" shaped exhaust ports and they are also about .1" higher on the head than regular heads (this shouldn't make much of a differance). The way I installed the headers was I already installed the engine and had the car up on jackstands. They went in really easy from under the car. As far as the engine install was.....very easy.....plug and play :yesnod:
As far as emissions, I don't know, my car :U 's gook out into the air and I don't care :lol: :lol: . Seriously, a you can advance/retard (can't remember which) the timing and mess with the carb a little to get it to pass 1977 emission standards without a cat, but it should be fine with the cat installed.. It might run like crap to the inspection but after you get the little sticker you'll be in business.
John

BSeery

Check out my ZZ4 project page at http://temp.corvetteforum.net/c3/bseery/zz41.htm --
mine has not pased emissions yet, but that is a carburetor problem, not an engine problem.

joshc

Bryans web page will give you a lot of details.
What I encountered. was ram horn manifolds will need to be ground down slightly in order to clear the valve covers. Short neck water pump will be needed. Plastic timing chain cover will need be modified slightly for a bolt. Potential for flywheel mod if with a manual trans. Recommend new carb to feed the ZZ4, and all of the other while you are in theres when swapping out.
there was probably more, but my mech. did the work and this is all that comes to mind off of the top of my head.

Good luck, you will enjoy.

joshc

Sorry, also forgot, emission in AZ were no problem with timing adj., and leaning out the carb. I dont have a smog pump, somehow been slipping past the AZ inspectors, no egr, and a high flow cat.

If anyone does need the specifics on emissions, post back up and I will put them on this post.

C3Vettesrock

How do you not have to do emissions test?