Thread: ZZ4 Crate Motor Timing - White mark on balancer?

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Hi, new to the forums here...I've read hundreds of posts the past year while building my car...found lots of info here, tremendous help!

I installed a new ZZ4 350 crate motor, and just started breaking it in. Went to set the timing and noticed a white paint mark on the balancer on the line at 4 degrees BTDC, It must have been put there by the tech at GM. Whats the deal with that? I know the ZZ4 should be set to something like 10 degrees BTDC. Does GM recommend 4 degrees? Anyone else have this white paint mark? I just want to make sure that its not there for some specific reason.

Thanks for your help.

12° BTDC @ 800 RPM, 36° total @ 3,000 RPM with vacuum advance line disconnected and plugged. This setting will produce 36° of total advance at wide open throttle (WOT).

There is apparently some mis information at various places indicating 32 deg total timing for the ZZ4

Thanks Robot,

So I guess Ill just ignore that white paint mark at 4 on the balancer. Perhaps this was set by the tech at GM just as a ballpark to start the motor.

Yeah, noticed the vacuum advance on the distributor provided way too much advance at high rpm's so I just plugged it and now its much better, what was GM thinking?? Right now I have it at 14 degrees @ 800 which is giving me about 38 total at WOT, seems fine, but if it pings I guess I'll drop it off a bit.
Thanks!