Tuning and timing advice

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Sep 24, 2018 | 04:32 PM

Jimbonanmis

Thread Starter

Junior Member

Joined: Feb 2018

Posts: 50

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From: Tampa fl

Car: 90 rs 58chevy

Engine: 383

Transmission: T5

Tuning and timing advice

Alright so I finished up my swap about 2-3 weeks ago 383 demon 650 mech sec no choke with rpm air gap and billet msd dis etec aluminum heads and unfortunately I don't know the compression but I used 93 octane and would get run ons so I added octane booster and jumped it to 95 seems to not run on but still sluggish.also has old serp system on it.the problem I'm having is tuning the carb well enough for the engine. I live in Florida so the choke I can live without. So I first put the engine on I believed to be tdc the first time puff of vapor second time moved dis 180 and cranked up and ran pretty decent adjusted idle and played with the mixture screws to a somewhat of a good mixture fuel pump is on a switch still factory tbi fuel pump going to the Mallory fpr.the psi is set to 6 seemed alright for the time being then the morning i would flip the switch hear to grunts from regular the pedal twice and it would start then later in the day when I'm going home from work I'll flip the switch hear no grunt check gauge and it's reading 4-5 I try to start and a puff of smoke comes out I try again while playing with throttle and get it going then it runs rough the whole way home I just changed fuel filter yesterday and I have a return from regular to tank but I'm seriously stumped anyone have any ideas?

Sep 25, 2018 | 07:36 AM

sofakingdom

Supreme Member

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Joined: Sep 2005

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Car: Yes

Engine: Usually

Transmission: Sometimes

Axle/Gears: Behind me somewhere

Re: Tuning and timing advice

Read and follow the Holley Tuning sticky in the Carb forum. The Demon works pretty much the same way as a Holley does, therefore the tuning process is similar.

Sep 25, 2018 | 10:30 AM