Supercharged spark advance question.
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
Supercharged spark advance question.
Alright, got the beast running this weekend and (aside from a few unexpected leaks and a set of glowing headers, all went well).
I'm looking for a general (read "safe") timing range to break this thing in at until I can get it dynotuned. Car is/has:
1986 Stock bottom end L98
AFR 195's
Superchaged
224/234 @ .050" .465/.488 cam
42# injectors
new large intake, runners, plenum
LT headers
MSD BTM
Alky injection
While I was breaking in the lifters,I noticed the glowing headers. So I quickly brought the timing to where the total advance read 43.6 at 1512 rpm. I'm not sure if that's high or low. I had the BTM set at 2.5*/psi when I shot it around the block for a few minutes, just to be safe, but I never reached above atmoshperic. I can't time the initial, since I had to bring it up so high (+10*) to solve the header issue, but I may have gone too high in my haste to cool off the exhaust. What do you guru's think?
I'll get an idle reading this evening when I get home. But can someone point me in the right direction?
Thanks!
I'm looking for a general (read "safe") timing range to break this thing in at until I can get it dynotuned. Car is/has:
1986 Stock bottom end L98
AFR 195's
Superchaged
224/234 @ .050" .465/.488 cam
42# injectors
new large intake, runners, plenum
LT headers
MSD BTM
Alky injection
While I was breaking in the lifters,I noticed the glowing headers. So I quickly brought the timing to where the total advance read 43.6 at 1512 rpm. I'm not sure if that's high or low. I had the BTM set at 2.5*/psi when I shot it around the block for a few minutes, just to be safe, but I never reached above atmoshperic. I can't time the initial, since I had to bring it up so high (+10*) to solve the header issue, but I may have gone too high in my haste to cool off the exhaust. What do you guru's think?
I'll get an idle reading this evening when I get home. But can someone point me in the right direction?
Thanks!
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
You should have no problems running stock timing settings. You may be running lean, (custom computer chip) tuning is required for boosted applications. BTW, what is your scr? The BTM and the factory spark retard should keep you out of trouble. The headers were glowing because you were running the rpm's up without loading the engine, possibly causing a lean-run condition.\
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
I'm running a custom Blowerworks chip, but it was burned prior to the cam and heads install. The set up is a Vortec V-2 SQ with 10# pulley. I'm going to bring the timing back to stock and check it again (once I fix my blower feed line leak).
