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MSD Ignition LS1 LS6 Timing & Rev Control - Build An Ignition Curve

We show you how easy it is to convert a Gen III engine to a carb with the MSD LS6 Ignition-Control Box.

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The springs and weights in a mechanical-advance distributor determine the rpm at which the advance curve begins and ends. Basically, heavy weights with light springs begin and end the advance curve at a lower rpm. The same weights with heavier springs require more rpm to eventually create the same total mechanical advance, which requires a higher rpm to achieve maximum timing. The total mechanical is determined by the length of the slot and diameter of the pin. For most street engines, a good curve should have achieved total mechanical advance by 2,800 to 3,000 rpm.

Vacuum advance is used to create additional ignition timing at part-throttle, light load conditions when there is very little cylinder pressure. Low cylinder pressure requires advanced ignition timing because the air and fuel in the cylinder are less dense, which means it burns slower. A vacuum-advance canister located on the outside of the distributor is connected to a ported manifold vacuum source on the side of the carburetor that sends manifold vacuum to the canister only after the throttle is opened slightly. This prevents creating vacuum advance at idle. The travel created by the vacuum-advance canister pulls on a plate in the distributor that advances the ignition timing. Adjusting the amount of travel is one way to adjust the amount of vacuum advance. This timing is only added at part-throttle. As the throttle opens and load is applied, manifold vacuum drops, reducing the amount of vacuum advance. At WOT, there is minimal manifold vacuum and no vacuum advance.

Each engine is different in terms of when and how much timing it needs. This is where tuning comes in. By messing with total advance for maximum power and vacuum advance to optimize cruise efficiency and fuel mileage, you can create a very happy street engine that runs better and uses less fuel, all without spending much money.

PARTS LIST
DESCRIPTION PN SOURCE PRICE
MSD 6LS-2 controller 6012 Summit Racing $357.10
MSD LS1/LS6 controller 6010 Summit Racing 312.70
MSD extension harness 60101 Summit Racing 184.10
MSD handheld monitor 7550 Summit Racing 154.80
SOURCES
Autotronic Controls Corp. (MSD)
El Paso
TX
9-15/-857-5200
msdignition.com
Summit Racing
P.O. Box 909
Akron
OH  44309-0909
800-230-3030
www.summitracing.com
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1 comments
The Don-#002
The Don-#002

great, how about a article on working a 6al2 programable with a hall effect with the allowance for boost retard.also with various msd coils available, not std ones as shown here that were hooked into

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