GT40s.com - View Single Post - Vacuum advance

Howard Jones · 02-12-06, 11:09 PM

I have a billet small cap MSD no vac advance with 6AL box. SVO 345HP 302, 9.5 to 1 CR, alum X heads, B cam, rpm performer eldenbrock, 750 holley doublepumper with mechanical secondaries.

I run the advance curve all in (35degrees) at 2600 rpms. static advance works out to about 12 degrees BTDC.

Car starts every time first crank with very little or no choke. Makes very good low end <4000rpms and pulls well up to 6K where I have it limited.

I use Calif. 91 octane unleaded.

I wanted to keep it simple to tune with mechanical everything. Works good and I can run the car about 230 miles at 80mph, 3.44 final, on a load of gas, approx 14 gals, without running it down to fumes. Not real good but I wasn't going for fuel economy when I built a GT40.

02-12-06, 11:09 PM	#7 (permalink)
Howard Jones 10 tenths Join Date: Jun 2002 GT40: San Francisco Bay Area California USA Posts: 1,921 Rep Power: 26	Re: Vacuum advance - is it needed? I have a billet small cap MSD no vac advance with 6AL box. SVO 345HP 302, 9.5 to 1 CR, alum X heads, B cam, rpm performer eldenbrock, 750 holley doublepumper with mechanical secondaries. I run the advance curve all in (35degrees) at 2600 rpms. static advance works out to about 12 degrees BTDC. Car starts every time first crank with very little or no choke. Makes very good low end <4000rpms and pulls well up to 6K where I have it limited. I use Calif. 91 octane unleaded. I wanted to keep it simple to tune with mechanical everything. Works good and I can run the car about 230 miles at 80mph, 3.44 final, on a load of gas, approx 14 gals, without running it down to fumes. Not real good but I wasn't going for fuel economy when I built a GT40.