my friend just advanced his timing from 6BTDC to 10BTDC and said it made a huge difference. I set mine to 6BTDC but think i'll advance it more. Where should i set it? my plugs are 2 heat ranges colder than stock with compression only .2 higher than stock so that should curb any preignition/detonation unless i really advance it. i run at least 91 octane. rest of car's specs are in the sig.

 

Go as far up as 12. Do it 2 degs at a time & see where it runs best.

 

Thats a good queastion. I wanted to advance mine, but I don' t know what its set at now. I want to put my 100 jets in so I figure I'll have to retard it buy 3-4 deg. But I don't know what to start it.

When does detonation commenly occur in a 10:1 comp. motor?

 

can't be done guys.

Ambient temp, engine operating temp, cam design and mixture quality (there are about 1/2 dozen others-like drivetrain config and weight) all play a role. Regardless of how good someone says he is at tuning,, you can't do that on the internet.

now.. where U start:
Find out how much you are getting from the mechanical advance in the distributor. Shoot for about 36-37 total. If you have to and the motor has a little cam, give up some mechanical advance to allow a little more initial advance.

The sweetspot on most mild 350s is 8 to 12 degrees initial and a max of about 20 in the dist (most factory dists don't allow that much internally).

 

How do I find how much machanical advance I'm getting?
How do I find my initial timing?

 

they are about 50-60bucks but well worth it. You can also put a timing tape on the harmonic bal. but it is harder to read when the motor is pulling a few rpm.