I'm running a mild cam, Holley carb, headers, and Mallory ignition on my '74. Any thoughts on proposed initial and total timing; I was thinking 12/36, respectively.
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Panteras built in 1972-74 ran a camshaft that Ford installed 4 degrees retarded, for emission puropses. If the timing cahain has bee replaced, new crank sprockets have three grooves, so the cam can be set to 4 degrees retarded (stock), straight-up (zero degrees) and 4 degrees advanced. We usually set the cams to 4 degrrees advanced since rapid initial wear will soon drop it to straight-up, the most desirable point.
Once the cam is set, depending on what it is, you may find that slightly different initial & total will suit you driving style (an local octane!) All engines are a little different in what they need, but your numbers should be pretty close.
Once the cam is set, depending on what it is, you may find that slightly different initial & total will suit you driving style (an local octane!) All engines are a little different in what they need, but your numbers should be pretty close.
As always - thanks Jack!
Your choice, 12 degrees initial timing and 36 degrees total timing, sounds like a good starting point. Your particular engine components (and gasoline octane) will determine if it is optimum.
Short of access to a dyno, I would fine tune initial timing by increasing it until the engine is a little hard to start, and then back it up in increments until it isn't. There, if the idle (speed and smoothness) suits you, and the car accelerates well, with no pinging, you're pretty close. Now to total ignition advance: The car will tell you if it is excessive, because it will overheat, or it will ping, or it will not accelerate as strongly at speed. (One, or two, or all) I'd bet 36 degrees will make the ol' gal grin from ear to ear.
Good luck!
Short of access to a dyno, I would fine tune initial timing by increasing it until the engine is a little hard to start, and then back it up in increments until it isn't. There, if the idle (speed and smoothness) suits you, and the car accelerates well, with no pinging, you're pretty close. Now to total ignition advance: The car will tell you if it is excessive, because it will overheat, or it will ping, or it will not accelerate as strongly at speed. (One, or two, or all) I'd bet 36 degrees will make the ol' gal grin from ear to ear.
Good luck!
Thanks - Sketch
At what RPM should total advance be reached?
I think the manual says 2000
quote:
Originally posted by BD:
At what RPM should total advance be reached?
I just completed installing a Pro-Billet MSD distributor on 3859 this weekend and the intial timing is set @ 12~14, the mechanical advance in the distributor is set-up for 21 degrees with the springs set to have the advance timing in by 2500 RPM's (one light silver spring and one blue light spring). When I checked this set-up on the timing light and it is working great 35~36 degrees of total timing @2,500 RPM, I haven't done a test drive yet so I'll let you how well that went.