Carb pros lend me your knowledge. . .
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Car: 1986 Trans am
Engine: 5.3 LM7
Transmission: T56 6 speed
Axle/Gears: Dana 44 w/ 3.55's
Carb pros lend me your knowledge. . .
Hi all. I need to know a good starting point for the jet size on my carb. It's a holley 750cfm vacuum secondary dual feed fuel line, but non-double pumper. It's going on a 355 with trick flow heads, a 224, 230 @ .50 cam, and a performaer RPM air gap manifold. Has headers and exhaust as well. I'm expecting 400 or so HP out of the motor at the flywheel. Carbs are new to me and I just need somewhere to start with and tinker with from there.
I eventually want to go to a non-vacuum secondary double pumper carb in the future, but I'm trying to get it going with this one for now. Any help or info I can get, I'll take.
I eventually want to go to a non-vacuum secondary double pumper carb in the future, but I'm trying to get it going with this one for now. Any help or info I can get, I'll take.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Bolt it on and see how it runs with stock jetting. Go from there.
Most likely this is a 4160 style carb with secondary metering plate instead of secondary jets, correct?
Most likely this is a 4160 style carb with secondary metering plate instead of secondary jets, correct?
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Car: 1986 Trans am
Engine: 5.3 LM7
Transmission: T56 6 speed
Axle/Gears: Dana 44 w/ 3.55's
Re: Carb pros lend me your knowledge. . .
Yep, believe thats the one. My bro bought it originally and I couldn't find any part numbers on it anywhere. It only has idle mixture screws on the front facing bowl.....elec choke...basically an off the shelf auto zone carb i think.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The part number is the "List" number stamped on the front left corner of the choke tower.
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Car: 1986 Trans am
Engine: 5.3 LM7
Transmission: T56 6 speed
Axle/Gears: Dana 44 w/ 3.55's
Re: Carb pros lend me your knowledge. . .
it says 80508-3 and right under that, 1216. Hope that means something.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The 80508 does. It's a 4160 model 750 CFM vacuum secondary. Metering plate on the secondaries. Came with 72 jets in the primaries and 6.5 power valve stock. That would be a good place to start if it's been modified from there. It had a .025 accelerator pump squirter, going up to a .028 might help out. The secondary spring was plain, a Quick Fuel Technologies adjustable secondary housing is a very good upgrade for a VS carb.
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Car: 1986 Trans am
Engine: 5.3 LM7
Transmission: T56 6 speed
Axle/Gears: Dana 44 w/ 3.55's
Re: Carb pros lend me your knowledge. . .
The 80508 does. It's a 4160 model 750 CFM vacuum secondary. Metering plate on the secondaries. Came with 72 jets in the primaries and 6.5 power valve stock. That would be a good place to start if it's been modified from there. It had a .025 accelerator pump squirter, going up to a .028 might help out. The secondary spring was plain, a Quick Fuel Technologies adjustable secondary housing is a very good upgrade for a VS carb.
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