timing for vortec, carb'd hei 350
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timing for vortec, carb'd hei 350
I' m sure this posted some where but I could not find it. Late 80's roller 350, vorted heads, hei ignition, no computer, what is the timing spec?? I have it timed like a 70's 350 if I remember correctly and am now wondering if my carb issues are really timing issues.
Thanks
Rob
Thanks
Rob
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Quite often "carb" problems are actually ignition problems.
Vortec heads don't need quite as much advance as older SBC heads. 32 degrees total mechanical is usually all that's needed, vs. the 36 of the older heads.
Initial timing should be in the 8-12 range. And, you should have the vacuum advance hooked up.
Vortec heads don't need quite as much advance as older SBC heads. 32 degrees total mechanical is usually all that's needed, vs. the 36 of the older heads.
Initial timing should be in the 8-12 range. And, you should have the vacuum advance hooked up.
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Re: timing for vortec, carb'd hei 350
I was at 9, bumped it up to 12 and big difference, still carb fine tuning to be done but less of a hesitation and much better response. Thanks
Rob
Rob
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Car: 86 IROC
Engine: MAS Crate 350
Transmission: 97 T-56
Axle/Gears: 97 rear 3.43's posi
Re: timing for vortec, carb'd hei 350
Mine is at 32 total. Dyno tuned and that was DEFINITELY the sweet spot!
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Car: 1986 Camaro Berlinetta
Engine: 4 bolt 355ci
Transmission: Borg Warner T-5
Axle/Gears: 3.73 Posi Disc Rear
Re: timing for vortec, carb'd hei 350
I'm running 30-32 degrees of total timing. 10 degrees base.
Also running with the vacc pod on the distributor and both ports on my Double Pumper plugged. seemed to advance too much otherwise.
Also found with the Vortec heads a slightly hotter plug (Autolite 26's) did better after 1000 miles of mixed driving, then the Autolite 24's I had on there with traditional SBC iron heads.
Also running with the vacc pod on the distributor and both ports on my Double Pumper plugged. seemed to advance too much otherwise.
Also found with the Vortec heads a slightly hotter plug (Autolite 26's) did better after 1000 miles of mixed driving, then the Autolite 24's I had on there with traditional SBC iron heads.
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Car: 86 IROC
Engine: MAS Crate 350
Transmission: 97 T-56
Axle/Gears: 97 rear 3.43's posi
Re: timing for vortec, carb'd hei 350
I believe it was 10? Im not running a vac adv but would prefer to. Just havent gotten around to getting one on there.
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Car: 1983 trans am
Engine: Vortec 350 w/ a comp cam
Transmission: B&Mth350 2800holeshot
Axle/Gears: 10bolt 3.23's
Re: timing for vortec, carb'd hei 350
with my vortec setup i discovered that it needs alot of initial timing and only 32-34 total. i run 15 base timing with 33 total all in by 3000rpms and it seems to be happiest
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Car: 91 Firebird Formula
Engine: 383
Transmission: built 700r4
Axle/Gears: 4.11, 9inch
Re: timing for vortec, carb'd hei 350
what about sumthing with a dart iron eagle head
should i set the timing up for an old style head
should i set the timing up for an old style head
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Car: 1986 camaro Sports Coupe
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Axle/Gears: 3.42 gov lock
Re: timing for vortec, carb'd hei 350
So timing without the vac advanced on the hei distributer should be about 12* btdc? And 32 with the vacuum advance hooked back up?
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09-17-2020 08:26 AM
350, 383, base, carb, carburater, carburetor, conversion, head, heads, hei, initial, plugs, timing, total, vortec