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GMC Jim · 01-10-2003, 09:31 PM

I bought my HEI from a local rebuilt shop that specializes in these units... In order to get the performance expected the didtributor must be calibrated by a choice of advance weights and associated springs to match the advance curve of the engine it will be installed in....
... Example:--1971 402 BB eng---Centrifugal advance---0 degrees @ 900 RPM; 2 @ 1260; 16 @ 2500 and 30 @ 4400RPM. the vacumm advance should be 0 degress @ 8" Hg and 20 degrees @ 17" Hg...
......Each engine has its own advance specs....so the distributor should be calibrated to match the specific engine that will receieve the HEI installation.............Jim

01-10-2003, 09:31 PM	#4
GMC Jim Senior Member Join Date: Dec 2002 Location: Portland, Oregon Posts: 901	I bought my HEI from a local rebuilt shop that specializes in these units... In order to get the performance expected the didtributor must be calibrated by a choice of advance weights and associated springs to match the advance curve of the engine it will be installed in.... ... Example:--1971 402 BB eng---Centrifugal advance---0 degrees @ 900 RPM; 2 @ 1260; 16 @ 2500 and 30 @ 4400RPM. the vacumm advance should be 0 degress @ 8" Hg and 20 degrees @ 17" Hg... ......Each engine has its own advance specs....so the distributor should be calibrated to match the specific engine that will receieve the HEI installation.............Jim __________________ '71 GMC;fleetside;PB/PS/AC/CC/402 Eng./Custom Paint/110,000act miles/3 fuel tanks(52gal).