Ignition timing help

[73c20jim]

OK. Read all of the threads but still have a question.

With my vacuum advance disconnected on my HEI and initial timing (at idle) at 12 degrees BTDC, I advance the RPM above 3000 RPM and get 20 degrees total timing.

Does the vacuum advance (when connected) make up the difference to get to my recommended total timing of 32 degrees BTDC ??? or is my distributor not giving enough advance ???

Having only fooled around with total timing on my race car with no vacuum advance, my total timing was set at 38 degrees BTDC and it was simple to adjust.

 

[climb-101]

timing should prob be around 34 degrees if i remember right. how much vac advance does you dist have? 12 should be good i think for the initial. you can always put a timing light on it and rev it up to 3000 and see what its at.

 

[legopnuematic]

Does it have really heavy springs in it? Most HEI's seem to have right at 20 degrees of mechanical advance so at 12 base will give you 32 total. To me it seems like either an advance spring issue or something with the weights possibly binding or something of the sort.