[ebgto]

I've been reading all the timing / tuning threads, please excuse the real basic questions. Previous experience was with mild stock engines long time ago, and never got involved with real tuning. Starting to tune a fairly fresh, new to me 535 IA2, edelbrock heads. Can share more details as needed. Cam has been degreed, and I'm setting timing, watching engine temps etc. it has an MSD pro billet distributor and MSD 6AL box. Since nearly all time will be on street with an occasional track pass, should I just move to a distributor with vacuum advance before spending too much time with this distributor? I understand you set total and initial advance before messing with vacuum. Without vacuum advance though, and about 12* of initial advance, can higher engine temps at idle be expected without the vacuum advance?

Thanks!

[Schurkey]

Better part-throttle response, improved fuel economy, and potentially lower engine temperature would be my expectation when including a well-tuned vacuum advance unit.

[ebgto]

Schurkey thanks! Being this is not an original motor, any recommendations on distributors? Should I just go with the MSD Ready to Run series with vacuum advance? Looking for input and experiences on different brands, mech. Advance adjustability, reliability, etc.

[torqjunki]

It is really person preference on distributors as there are several to chose from. If you plan to make some long trips, may want to lean towards a custom built And tuned HEI. If you do have any component failures on the road, you can get parts at most any parts store. Can also keep a few spare parts in the car. There are guys on here that can set one up for you. Also DUI makes a nice unit. There are some decent cheap HEI's out there, but they need some tlc to make them reliable. Not sure what intake and car your working with, but make sure there is adequate clearance for the HEI.

[i82much]

r2r is well built and makes life easy. Could really use a crane style adjustable vac advance though.

[Cliff R]

I recommend using a vacuum advance for anything that sees a lot of street driving. It allows for a leaner A/F ratio for light throttle cruising, which improves fuel economy, engine power at light load, and less carbon build-up in the engine.

Very well thought out engine combos don't typically need a lot of timing added. Usually 10 to about 14 degrees is plenty.

You can also add the timing at idle speed if the engine likes, wants, or responds well to that much timing at idle (initial plus VA).

The target timing for cruise is around 42-48 degrees for most set-ups. Really low compression ratio engines, or somewhat over-cammed engines or combinations of both may want quite a bit more than that......Cliff

[ebgto]

Thanks all for the info. Now need to find a distributor.