MSD 8572 Distributor Tuning Question
Thread Starter
6th Gear
Joined: Mar 2010
Posts: 6
Likes: 0
From: Del Rio TX
MSD 8572 Distributor Tuning Question
Has anyone messed with the springs/bushings for getting the right timing curve for a 350? I know this depends on the specific setup of the motor. I've got the basic ones in that came installed in the distributor, and am looking for guidance on how to start troubleshooting different spring/bushing combos to tune the engine correctly. It runs fine without pinging but doesn't feel like it's putting out the power it should. Any tips would be helpful.
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Here is what to do.
1. Go to MSDIGNITION.COM and download the instrutions for setup of the Dist you have. This will cover the curves for springs and the total advance by the bushings. Very easy to change.
2. Send me your email address and I'll send you copies of Lar's info papers on timing etc. They will walk you through timing a chevy engine.
PS - You want the total timing "all in" by 2500 - 3000 rpm's and a total advance of 36 degrees. Start checking yours out as to what you have.
1. Go to MSDIGNITION.COM and download the instrutions for setup of the Dist you have. This will cover the curves for springs and the total advance by the bushings. Very easy to change.
2. Send me your email address and I'll send you copies of Lar's info papers on timing etc. They will walk you through timing a chevy engine.
PS - You want the total timing "all in" by 2500 - 3000 rpm's and a total advance of 36 degrees. Start checking yours out as to what you have.
Burning Brakes
Joined: Jun 2008
Posts: 1,086
Likes: 1
From: Michigan
Keep in mind that when people talk of total timing they mean base timing + mechanical advance and NOT including vacuum advance. Keep the vacuum line disconnected and plugged when checking total timing. The reason is that under WOT the vacuum advance isn't functioning due to the low vacuum at WOT.
Tech Contributor
Joined: Aug 1999
Posts: 14,377
Likes: 6,377
From: At my Bar drinking and wrenching in Lafayette Colorado
The "out-of-the-box" tune on the MSD distributors is extremely conservative: The curve is long and slow. In order to get the distributor to perform properly you need to install the fat limit bushing in order to shorten the curve, and you need to install the softest springs in the kit to get the total advance in at 2500-2800 rpm. The short curve will allow you to get your initial timing up into the 16-18 range without exceeding 36 total.
Lars
Lars
Burning Brakes
Joined: Jun 2008
Posts: 1,086
Likes: 1
From: Michigan
As usual Lars is right on. Here are the curves for the MSD distributor. I like graph E with a blue bushing and one light silver and one light blue spring. The initial timing can then be set at about 13*. Graph F with 2 light silver springs works too but I didn't want the advance kicking in so close to idle.
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