VACUUM ADVANCE QUESTION?
 

Hello all

question is ,

Do you guys run your vacuum advance to your distributor?

can you run your motor without? does this help/hinder performance?

what exactly is the purpose if you have a mechanical advance already?

I read somewhere about guys not using their vacuum advance and was just inquiring.

Thanks

Fine for track, It will run ok, Your mileage will suffer without the vac advance

If your distributor came with a vacuum advance use it. If it's a mechanical one and you can adjust the timing curve then go for 10 degrees initial timing and build the curve to bring in 25 more degrees of timing at 2500 rpm.

Here is a good read on the subject: http://www.firstfives.org/faq/timing...ed_engines.PDF

http://www.youtube.com/watch?v=tZnR107Gu0E

http://www.youtube.com/watch?v=cFfne...feature=relmfu

Thanks for all the advice that makes things a lot clearer.

i have the vacuum advance on and plan on leaving it

thanks again

happy new year

S -

This is my experience with vac advances on MODIFIED BIG BLOCKS with a 'performance' type dist. (Note the caps.)

No, you don't need it, providing you're getting both your initial and total advance in the range you want. As far back as I can remember, no one left it connected on MODIFIED BIG BLOCKS with a 'performance' type dist. (Note the caps.)

Bottom line: try it for a week or two both ways (it readily reversible) and see if you notice any difference or if one clearly works better. (Yes, you will probably have to retime between tests.)

Archer

On my cruiser 318 Aspen with a 4 speed tranny vacuum advance all day long for good performance and gas mileage. On my 440 Dart with high lift cam and all gear spinning tires. MSD pro-billet with mechanical advance. 10 degrees initial timing...curve set at 25 degrees all in at 2,500 rpm.

I don't run vacuum advance on my car... timing set at 36 degrees for drag racing and burn offs.