View Full Version : Timing for the GM ZZ383


xtratuff
Jul 1st, 07, 02:41 PM
I just installed the ZZ383 in my 68 camaro and am still trying to get the timing set just right. Every time I call GM for advice I get a different answer as to what to set the timing at. Can someone shed some advice on what they have their ZZ383 set at.

mnm99
Jul 1st, 07, 06:16 PM
I just installed the ZZ383 in my 68 camaro and am still trying to get the timing set just right. Every time I call GM for advice I get a different answer as to what to set the timing at. Can someone shed some advice on what they have their ZZ383 set at.

I believe it stated 32* total with vac advance disconnect. Initial around 15*Here's what I found.http://www.gmperformanceparts.com/EngineShowcase/tech_specs.jsp?engId=ZZ383&engine=ZZ%20383&sku=12498772&engCat=sb


As for calling GM...They suck. I emailed them 3 times and never got a response. I tried calling GM performance, GM goodwrench and the headquarters..Nobody could tell me anything. The only awnser I got was to call the dealer I got it at. They also were good for nothing.

Fred Mertz
Jul 1st, 07, 08:48 PM
What does GM do to their motors that would require anything but 36 degrees all in by 2800? This figuring 12 initial with 24 in the dist and full vac advance on top of that. Isn't this setup pretty much standard these days for performance motors running on quality gas?

Just wondering why it would be different. Warranty issues?

DjD
Jul 1st, 07, 09:16 PM
Fred from the postings here and my personal experiences with my 383 stroker 34 total seems to be the median total all in between 2800-3000rpm. A shorter stroke sbc seems to run 36 - 38 total. Of course this really depends on cam timing and to some degree gear ratio...

BPOS
Jul 1st, 07, 10:19 PM
What does GM do to their motors that would require anything but 36 degrees all in by 2800? This figuring 12 initial with 24 in the dist and full vac advance on top of that. Isn't this setup pretty much standard these days for performance motors running on quality gas?

Just wondering why it would be different. Warranty issues?

Nope - it's the combustion chamber design. It promotes faster burning of the mixture, hence the term "Fast burn". The Fastburn heads like 32 total - you might be able to sneak it up to 34. Mine runs best at 32.

Dirt Reynolds
Jul 2nd, 07, 04:08 AM
The 2007 GMPP catalogue says the ZZ 383 timing specs are 10° initial and 32° total.