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I do not have the service manuals. Someone sent that info to me via email pdf.
If someone has a 80s Chrysler Marine Engine manual, please look up this info for all of us.
I have the manuals and I directly quoted the numbers given in the last chrysler 440 timing curve thread. They are similar to the numbers above. They seem very vague as the above numbers are.
I am about to replace my carbs with Edelbroch 1410's next weekend. I will try to map out the curve on each engine. If they match, we should be good.
Greg,
I'm sorry we don't know exact the advance curve for the Chrysler marine
engine. Normally my customers are using the springs already installed on the
distributor. That would be my suggestion.
If, you wanted to try another combo. I would remove one of the silver
springs and replace it with one cooper. If, you get any pinging then you
would need to go back to both silver springs.
Marvin Grebow Jr.
PerTronix Inc.
Technical Department
909-273-6006
[email protected]
I'm not arguing with you.... I'm just observing what you saw and what you posted here.Checked my numbers this past weekend.
My factory new Pertronix distributors I installed have the following curve....
5 deg base + advance = Total advance
If this includes the total advance at the "full in" rpm, that would be correct!
IOW, what you see at the crankshaft in degrees, and at the full-in RPM = TA (total advance).
5 degrees at 800 RPM
5 degrees at 1000 RPM
That sounds correct, since we don't require any mechanical advance any sooner than 900-1,000 rpm.
We have to remember that most Marine Ignition curve graphs do not include BASE advance. They show distributor advance only!
We also must remember that BASE is always part of what we see when we strobe the timing marks dynamically. It can't help but be included!
5 degrees at 1500 RPM
Does this mean 10* actual advance (base of 5 + 5 = 10) @ 1,500 rpm?
8 degrees at 2000 RPM
Does this mean 13* actual advance (base of 5 + 8 = 13) @ 2,000 rpm?
22 degrees at 2500 RPM
Now I'm a bit confused!
Why the large jump in just 500 rpm...., and does this include BASE?
Looks like you did not include BASE in the previous numbers... so if we add BASE of 5*, this would be 27* @ 2,500 rpm.... correct?
22 degrees at 3000 RPM
Why no increase in spark lead from 2,500 to 3,000?
If this is full-in, it would have been full-in @ 2,500 rpm!
22 degrees at 3500 RPM
Again, why no increase in spark lead from 2,500 to now 3,500??
Again, if this is full-in, it would have been full-in @ 2,500 rpm!
IMO, 2,500 rpm is a tad bit too early to be full-in.... but I"m by no means a Chrysler Marine expert!
Now what
1.... All numbers listed are total advance. I have a mechanical limit of 22*
2.... The fast jump between 2000 and 2500 seems a bit much. Could have been because that was the first high rpm run of the season and it could have been a little sticky. I will double check it soon.
any idea where ican get springs for the counter weight in my prestolite dist. should the be different or both the same??