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Discussion Starter #1
I'm schooling myself about ignition timing on here and think I have it figured out.

I have a Pertronix distributor that I'd like to play with the timing a bit. I have the spring and mechanical limiter kit to go with it. There is a chart that was included and it indicates the crankshaft degrees as the RPMs increase depending on what color spring is used, with the max crankshaft degrees of 24*. Is crankshaft degrees the same as mechanical advance? If it is, then I'm guessing that with 24* of mechanical advance along with the 14* of initial timing that I'm running, then total advance is 38*. Is this correct?

There are limiters included with the kit that will limit the mechanical advance to 12*, 16* and 20*. Before I start throwing springs and limiters around, just want to make sure I'm reading this correctly.
 

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My personal feeling is to run as much initial as you can without having hard start or pinging especially if you're running a hotter cam. I would shoot for something like 20° mechanical in the distributor. The more initial timing, the more it's going to pick up the lower end.

A FB friend of mine has a 63 Fairlane on a circle track suspension. His engine in a 289, E Street heads, Thumper cam a 80's Ford 2 barrel aluminum intake, yes you read that right and a 500 cfm Holley 2 barrel. I think it's for class rules. It makes 360 or 380 hp. He has his distributor locked out, no mechanical advance at all. He has his initial timing at something like 36° BTDC. He was telling me at first it just didn't run well, lazy. He said he locked up the distributor, with all that timing in right away fixed the drivability problems. He sent me a clip where he just hit the key from outside and it fired right off without any issues
 

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Messed around with it some. I found a post from several years ago that detailed on how to set it up. I put the lightest springs on with the 20* limiters on it, and it was a fail. The light springs are too light and the timing wouldn't drop back down to the initial 14* - it would stick at about 25* degrees just by blipping the throttle from under the hood. Left the limiters on and went back to the middle (silver) springs and it worked. Went for a test drive and when I came back, the timing had settled back down to 14*. I've got a couple of Motorcraft dual point mechanical advance distributors to play around with, so I'm going to put the points back in one and see what I can do with it.
 

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Messed around with it some. I found a post from several years ago that detailed on how to set it up. I put the lightest springs on with the 20* limiters on it, and it was a fail. The light springs are too light and the timing wouldn't drop back down to the initial 14* - it would stick at about 25* degrees just by blipping the throttle from under the hood. Left the limiters on and went back to the middle (silver) springs and it worked. Went for a test drive and when I came back, the timing had settled back down to 14*. I've got a couple of Motorcraft dual point mechanical advance distributors to play around with, so I'm going to put the points back in one and see what I can do with it.
Are you running full manifold vacuum or ported vacuum to your vacuum advance. If running full vacuum that maybe why you were hanging timing.
 

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Discussion Starter #5
Are you running full manifold vacuum or ported vacuum to your vacuum advance. If running full vacuum that maybe why you were hanging timing.
I wasn't running any vacuum to the distributor at the time.
 

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Discussion Starter #7
@LeeFred hey can you post the link to the article you found please ?
I am doing the same kind if research for my car
Let me see if I can find it again.

EDIT: That didn't take long -

 
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