thehazmatguy
03-20-2008, 10:57 PM
I have a ZZ4 that hasn't been installed yet. I need to ditch the HEI that's included with the ZZ4 because of clearance issues. I have an MSD distributor 8261 to replace it.
The ZZ4 webpage at GM performance parts spes the ignition timing as:
10 degree BTDC @ 800 rpm 32 degree total @ 4000 rpm with vacuum advance disconnected
http://www.gmperformanceparts.com/EngineShowcase/tech_specs.jsp?engId=ZZ4350&engine=ZZ4%20350&sku=12499712&engCat=sb
So, should I:
Subtract the initial 10 degrees from the 32 total, and set the weights and stop in the distributor to go 22 degrees at 4000 rpm?
As I read it, that just happens to be the MSD set up right out of the box. MSD states that's the slowest advance curve possible.
I'm wondering if I should skip the suggested curve on the GM website and choose an ignition curve in the middle of my choices and work from there?
The ZZ4 webpage at GM performance parts spes the ignition timing as:
10 degree BTDC @ 800 rpm 32 degree total @ 4000 rpm with vacuum advance disconnected
http://www.gmperformanceparts.com/EngineShowcase/tech_specs.jsp?engId=ZZ4350&engine=ZZ4%20350&sku=12499712&engCat=sb
So, should I:
Subtract the initial 10 degrees from the 32 total, and set the weights and stop in the distributor to go 22 degrees at 4000 rpm?
As I read it, that just happens to be the MSD set up right out of the box. MSD states that's the slowest advance curve possible.
I'm wondering if I should skip the suggested curve on the GM website and choose an ignition curve in the middle of my choices and work from there?