MSD springs and bushings

[shatar4]

Is there a formula in figuring the right combo setup with the springs and bushings or is it a hit and miss type thing?

[Chryco Psycho]

of the 6 possible curves I usually head for the last 2 with the most aggressive curves & shortest advance
most built engine want more initial timing so the shorter curve helps , as long as the engine doesn`t start to ping under accelleration I use a fast curve & back off if pinging occurs

[shatar4]

I tried both combos and the 2 light silver springs wins hands down. What a difference. Thanks a bunch. Now to work on a overheating issue. 

[Chryco Psycho]

 

[Roppa440]

With a bigger camshaft you might even find that the biggest bush (least timing advance) is still not enough to give you enough initial.

With your engine at idle advance the timing until you hear the rpm just start to level off. Then back the idle speed off on the carb and try a few hot starts to make sure it still starts OK without kicking back or stressing the starter. If all is well put your timing light on and see what the initial is. Then remove enough timing from the distributor to allow you to run that much initial.

You will find your engine and headers will run a lot cooler.

[solarguy]

FBO makes an MSD bushing 1 step bigger than the black one to gain more initial timing.  I bought one to use at my next tune up. 

http://www.4secondsflat.com/MSD%20Distributor%20Tuning.htm

[shatar4]

So if I change either the springs or bushings, I would have to reset the timing?

[Oldschool]

I am running the MSD unit with the timing locked out. I have no springs or weights in the dizzy. I set the timing at 36* and that is it. The Hemi runs fine with no ill effects.    

[Roppa440]

Yes if my cam was a little bigger I would probably lock the timing out too.

[Roppa440]

So if I change either the springs or bushings, I would have to reset the timing?

yes. Just remember you need more initial and your engine will run cooler.

[shatar4]

Ok, I have both light springs in my MSD, rechecked timing. 16* initial, 34 total. Took it for a test drive and running alot cooler but a slight pinging. Should I put the blue spring and a light silver spring and re-time it to stop the pinging?

[moper]

Use one light silver, one blue. If you don't touch the distributor base you don't have to re-time. I was going to say I've never run two light silvers on a street car without having problems with pinging. Almost all of them like the lt silver/blue combo unles they have a stock or really low convertor or gear.

[shatar4]

Thanks Moper. I'll change it tomorrow. It runs great except the pinging.