Thread: ? about a bbc running 8 degrees btdc, total 30 degree at 3200 rpms

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I'm running 28 total so I can use 91 octane gas. I do have vaccum advance also. Its adjustable and is set for 10 to 15 deg. of advance. I get 13.3 mpg if I behave. BBC 454+.030- 10.7:1 comp -Iron heads- comp 280H cam. 308 HP at wheels on 91 octane

In general vacuum advance helps with mileage, emissions, and starting on street engines. You can run fine without it as long as you have a distributor that you can tune the mechanical advance on.

In general BBC's with no vacuum advance like about 12 deg initial and a fairly aggressive ramp to 34-36 all in by 3000 rpm. I could believe there are those that like 8 deg initial as well. In general w/o vacuum advance you run as much initial as you (and your starter) can tolerate.

Will it hurt anything? I don't think so as long as there is no detonation due to being too far advanced and you have a decent starter. 8 deg initial should be easy on starter.

Kitz