Quote:
Originally Posted by Gregski
I hear you, thanks for sharing but aint that what the tiny alan wrench is for to twist and turn the adjustable vacuum pod to adjust the vacuum to your liking, as opposed to the non adjustable OEM can which lacked that feature?
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Yes but remember you are only affecting the rate of the vacuum advance portion of your total advance with that Allen trim screw. So let's say your vacuum advance will deliver up to 20 crankshaft degrees of ignition advance. You have set 12 crankshaft degrees of initial advance; so now you're POTENTIALLY up to 32 crankshaft degrees; and then your centrifugal or mechanical gives you another 24 crankshaft degrees beyond that, if you don't limit the vacuum actuator that would potentially be a total of 56 crankshaft degrees ignition advance.. way too much.
(note I have zero experience with the HEI)
I know what you are thinking and it does make sense that if you turn the Allen screw of the vacuum pot so that at your max idle 21 Hg it is only giving you a known amount of advance - but I think it is not recommended to depend on that - and I think that is why Crane also makes the adjustable stop plate and the stop plate and adjustable pot are meant to work together.
I feel bad bringing up timing if it hijacks your original overheating problem and there are such good posts already on this forum from people far more qualified than me. For example Bruce88 did a whole series on timing in his build post - starting with post #712 and it is just a masterpiece of logic.
I think if you have your initial at 12 BTDC and you are sure of your TDC and balancer mark and you set it with the vacuum advance disconnected and you know there was no centrifugal advance coming in at your 850 RPM idle that should be enough to eliminate insufficiently advanced timing as the cause of your overheating.
I guess if that is all the case and it were me I might then check to see if the heat is coming from your automatic transmission rather than the motor... assuming of course you are running the trans fluid through the factory heat exchanger in the radiator