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68gmsee · 07-01-2011, 10:43 PM

First thing I would do is to put the #1 piston at top dead center in the compression stroke and make sure the balancer marks aligns with the "0" on the tab. If it doesn't make a new mark and check to make sure balancer is not defective. The vacuum advance seems to be doing it's job if it goes from 20 retarded disconnected to 4 retarded when hooked up.

(to check for TDC if you haven't done it before)

Remove the plug and with your finger in the hole feel for pressure as the piston is coming up then slowly rotate the engine until it comes up to the very top. I usually insert a long screw driver and feel as it reaches the top. Some people say to buy a TDC stop.

07-01-2011, 10:43 PM	#3
68gmsee Active Member Join Date: Jul 2007 Location: Centrally located between Houston, Austin and Waco. BCS area. Posts: 7,947	Re: problem with HEI conversion First thing I would do is to put the #1 piston at top dead center in the compression stroke and make sure the balancer marks aligns with the "0" on the tab. If it doesn't make a new mark and check to make sure balancer is not defective. The vacuum advance seems to be doing it's job if it goes from 20 retarded disconnected to 4 retarded when hooked up. (to check for TDC if you haven't done it before) Remove the plug and with your finger in the hole feel for pressure as the piston is coming up then slowly rotate the engine until it comes up to the very top. I usually insert a long screw driver and feel as it reaches the top. Some people say to buy a TDC stop.