L46 w/MSD Questions
Thread Starter
Pro
Joined: Jun 2010
Posts: 620
Likes: 18
From: Travelers Rest, SC
L46 w/MSD Questions
Well after having my car a few months I noticed that under even light acceleration around 1500-2500RPM I could hear some detonation. So I decided to get a timing light today and I first realized that my tach was reading about 800RPM but according to the timing light, it was at 700. Adjusted the idle to 800RPM and then decided to check timing at idle and to my surprise it is set at 30*! The service manual calls for 12*, is it me or does that sound like a heck of a lot of timing at idle? I didn't even bother to check and see what timing is all in, I'd like to have idle timing sorted first.
My question is, being that this car has had its points replaced by an MSD distributor, would I still adjust timing the same way as a points type distributor? I want to say that I've heard about a module that can be replaced under the distributor that has a set timing curve but I'm not sure.
Thanks in advance!
My question is, being that this car has had its points replaced by an MSD distributor, would I still adjust timing the same way as a points type distributor? I want to say that I've heard about a module that can be replaced under the distributor that has a set timing curve but I'm not sure.
Thanks in advance!
Pro
Joined: Jun 2004
Posts: 543
Likes: 2
From: Miami FL
St. Jude Donor '11, '14
read the excellent sticky on ignitions by LARS at the top of the page and work from there. Timing is timing regardless of the technology used to create it.
Rob
Race Director
Joined: May 2006
Posts: 18,737
Likes: 2,583
read the instructions for your distributor, if you have more questions afterwards, please ask
http://www.jegs.com/InstallationInst...1/121-8571.pdf
http://www.jegs.com/InstallationInst...1/121-8571.pdf
Le Mans Master
Joined: Nov 2006
Posts: 7,215
Likes: 1
From: Orlando FL
as stated above, set the total timing, let it idle down and see what you got at idle. if the idle timing is high <18 degrees I would not even give it a second thought.
if the distributor is still in the stock configuration you should see about 20 degrees of difference idle to full advance say 14-34.
if its not then look into it and see what springs and advance stops are installed.
MSD makes kits to tune the distributor. Unfortunately lots of people tend to get the thing way out of whack.
good luck.
just go slow, ask questions if you have them don't get frustrated.
or drink too much beer during the tuning evolution
that's my typical down fall
if the distributor is still in the stock configuration you should see about 20 degrees of difference idle to full advance say 14-34.
if its not then look into it and see what springs and advance stops are installed.
MSD makes kits to tune the distributor. Unfortunately lots of people tend to get the thing way out of whack.
good luck.
just go slow, ask questions if you have them don't get frustrated.
or drink too much beer during the tuning evolutionthat's my typical down fall
Thread Starter
Pro
Joined: Jun 2010
Posts: 620
Likes: 18
From: Travelers Rest, SC
Well just got back in from the garage and the timing at 2500RPM was 45*, jeez! So I dialed her back to 30* at 2500RPM and that came out to 16* at idle. Haven't had a chance to drive it yet, but hopefully that will get rid of the detonation. I can already tell that it does idle a bit more smoothly.
Burning Brakes
Joined: Feb 2012
Posts: 925
Likes: 7
If this is a street car, you would benefit from having vacuum advance (better throttle response, cooler running at idle and cruise and better mileage). You need to have the 8572 model or see if your 8571 can be made to have vacuum advance.
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