Quote:
Originally Posted by taff2
Low ignition timing (retarded) can cause a pop back as Charlie said , it's best to have a boost adjustable timing box (MSD or built into an EFI ecu) so that you can run a fair bit of initial timing advance - 32/36 degrees or so-this will give you good throttle response and idle ,and then pull timing as boost increases. It's usual to start with pulling 1 degree per pound of boost and then add a degree back at a time, checking your plugs carefully. I would expect you to end up around 22-28 degrees total timing at 16 psi,maybe quite a bit more given your low compression ratio (for E85.)
|
I have an MSD Grid ignition with boost module so adjustments are easy. I'm hoping to bring the timing up to about 24-26 but won't know till back on the chassis dyno. So far it went to 16psi but I did not make a full pull yet.
Steve
__________________
67 Firebird 3440 lbs, Pump gas 537 IA2, tiger heads, 4.86 rear, 32 x 17.5's, full interior, 4 mufflers, street shape 1.36 60', [email protected] 1/8 mi. 5.67@123 on small shot.
|