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tkslr
09-08-2003, 05:42 PM
I use a 7AL3 box on a drag car, have been having intermittent starter kicking. No set pattern or reason, may only occur once or twice a night. Had start retard on solenoid and then connected to constant 12v for retard. My question is....con i connest on stage of the retard to my solenoid also to get an additional 5-10 of retartd or is 25 the total amount possible?
Thanx
Tom

msdtech1
09-08-2003, 07:54 PM
To correct the kickback problem, you need to identify why it is doing it only once in awhile instead of all the time. Adding more retard may make the problem worse if it is related to the firing position of the distributor. I take it that you are running a locked mechanical advance distributor or a crank trigger distributor with no mechanical advance. If so, have you ever chacked the rotor phasing while the engine is being started? If the rotor tip is far enough past the terminal on the cap that it is suppose to fire too then you may be experiencing crossfire in the cap. With no retard activated, the leading edge of the rotor tip should be right at the beginiing of the terminal in the cap when the spark occurs. This is important because when you hit the start retard the rotor will not fire for an addition 25 degrees of crankshft rotation, and in your case that may be past the terminal. Check the rotor phasing on the distributor just to be safe.

MSD Tech1

tkslr
09-08-2003, 08:01 PM
I am running a crank trigger with a locked msd billet distributor, rotor phasing is center of post while running (set with timing light through cap w/hole at post). Should it be moved to leading edge? Very good points, I appreciate your input.
Thanx
Tom

msdtech1
09-08-2003, 11:34 PM
Yes, try moving it to the leading edge and then activate your start retard to see where the rotor tip is positioned when it sparks. What you are trying to achieve is a position where the rotor sparks from the leading edge without any retard activated and then from the trailing edge when the most retard is activated. The spark will always jump from the sharpest point on the rotor tip that is closest to the cap terminal. I think you will be supprised how much the rotor moves when the start retard is activated. Let us know how it turns out for you.

MSD Tech1

tkslr
09-17-2003, 05:15 PM
Aligned rotor phasing per msd tech instructions, raced past weekend and started several times and the problem never occurred. So far so good, very well pleased with the knowledge and response from manufacturer. Message boards are a very helpful tool and I will definately use again.

Thanx
Tom

msdtech2
09-17-2003, 05:25 PM
Cool, thanks for posting.
msdtech2