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Holley adjust

1081 Views 8 Replies 4 Participants Last post by  zipchip
Hi, need some help with a diagnosis....just recently completed 70 454 (full Ls6 specs) full restoration with aftermarket Holley 850 dbl pumper, elec chock disabled, choke wide open. Carb rebuilt about 24 mos ago, ran in cam/engine, then carb sat for 12 mos before final re-install. Car has only 15 miles on it....plugs look fine, timing at usual 4 btdc.

Cold start is just fine, idle is good at around 750, no hesitation, float levels good...when engine is hot having two issues

1- Engine diesels loudly at shut down (rpm at 750)
2- Hot restart is a problem, engine cranks and acts and smells like it is flooded, will start with pedal to the floor.

Any suggestions? Also need a book or website on tuning and adjustments for a 850 dbl pump.

1 - 2 of 9 Posts
vacuum advance is capped/fixed at 20 initial
Your not using vacuum advance in your total are you ?
The centrifugal (mechanical) advance should be set to a max of 20 and the initial set to 16.
The vacuum advance doesn't count in the total timing.
1 - 2 of 9 Posts
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