Timing and Dieseling Issue

[Roadcuda]

Hamden on Wedneday for 4 hours and Old Saybrook today for 4 hours ��

Four hrs for Old Saybrook is a long time. At one time you could get in and out in 90 minutes.

 

[moparchris]

Hey Collin, I may be of some help here. Like others said throttle position and timing will help with dieseling. But lets take a deeper look. When you turn off the key the ignition is interrupted. So that alone should tell you that there is another ignition source. This source is a hot spot inside the combustion chamber. It could be some casting flash or a spark plug. Retarded ignition timing drives up exhaust temps and the exhaust valve becomes an ignition source as well. In my experience one of the three things I mentioned is the culprit. Now you can fix the issue by A. closing the throttle as much as possible B. advance the timing a few degrees C. Put in 2 step colder spark plugs or D. Race Gas. What Chrysler did to fix the six pack/ six barrel cars is install a solenoid that closes the throttle ( it actually holds the throttle open when the key is in the run position and then closes the throttle when the key is off) when the key is shut of. You can install a anti dieseling solenoid with harness to your car pretty easily. I doubt cam timing has a whole lot to do with it nor the compression ratio. Like Bob said aluminum heads will help because it will probably eliminate any hot spots in the chamber. What I do is just shut it off in gear and if its a 4 speed (which if my crappy memory serves me correctly, it is) let the clutch out a little to load the motor as you shut it off.

 

[IQ52]

Yeah, this being a street car the logical thing to do is blend in race gas all the time. I would never consider lowering the compression ratio with a simple head gasket change to correct for a poor compression ratio/camshaft combination.