having problem wth getting initial timing right now i have 22 to 24 degrees is that to much i have a 454 compcam 527 lift 292 - 312 brand new msd street fire dist. trying to figure out do ineed to do something to dist.?
Set the initial timing advance with the vacuum advance disconnected and the vacuum source plugged and the engine idle speed adjusted as low as possible or less than 700 RPM. After the initial timing advance is set, re-connect the vacuum advance and adjust idle speed. This method of initial advance adjustment is for a stock engine. If your engine is equipped with a radical cam and has less than 14 Hg vacuum at idle, you cannot use this method. A radical camshaft and low engine vacuum requires the total timing advance to be adjusted at 3500 RPM.
Initial timing with more than 14 Hg engine vacuum:
9.5:1 to 13:1 compression ratio.....Initial advance: 10 to 12 degrees BTDC
8.5:1 to 9.5:1 compression ratio.....Initial advance: 13 to 20 degrees BTDC
At 1200 RPM, the centrifugal advance is pulling 12 degrees advance and the vacuum advance is pulling 12 degrees advance and are in addition to the initial advance. Your total advance should be about 35 degrees BTDC at 2500 RPM which will leave 11 degrees BTDC initial advance. The 24 degrees BTDC you have indicates your initial advance is 0 degrees BTDC. Using a cheap Pep Boyz tach/dwell meter, turn the distributor until the total advance is 35 - 38 degrees BTDC at 2000 to 3000 RPM.
Engines with radical camshafts and low manifold vacuum require the total timing advance to be set at 2500 to 3000 RPM. The centrifugal advance, vacuum advance (if any) and initial advance must be combined to give the total of 35 - 38 degrees BTDC checked at 2000 to 3000 RPM. Turning the distributor will adjust the initial advance.
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