carburetor size
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need some information about the motor before anything can be said.
www.devanecarbs.com
www.devanecarbs.com
DeVane carburetors are precision assembled and calibrated to YOUR combo. Are you ready for the next level of performance?
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I've have a number of customers running 1000+ CFM carbs on 350 / 351 cid inch engines, and 900+ cfm carbs on 289 / 302 cid engines, street and strip, consistently.
One, ran a '69 Mach 1 with a .030" or .040" over windsor with Vic Jr. heads in the heavy car launching at 2800 - 3000 rpm. Oh, did I say he also runs at between 8600' and 9000' DA?
True, you can't expect to do this with a stock carb Holley or not, but you can go bigger than most people think with good annular boosters and further still with a good tune in the carburetor. When I say tune, I mean fuel curve that is correct for the engine in the vehicle.
Troy Patterson TMPCarbs.net TMP Carbs
One, ran a '69 Mach 1 with a .030" or .040" over windsor with Vic Jr. heads in the heavy car launching at 2800 - 3000 rpm. Oh, did I say he also runs at between 8600' and 9000' DA?
True, you can't expect to do this with a stock carb Holley or not, but you can go bigger than most people think with good annular boosters and further still with a good tune in the carburetor. When I say tune, I mean fuel curve that is correct for the engine in the vehicle.
Troy Patterson TMPCarbs.net TMP Carbs
To restate Troy's position: Big carbs are much more tricky to tune and are likely to be a power plus only if set up very precisely. If you can't make that happen, a conventionally sized carb {rated CFM = [(peak power RPM /2) x displacement]/1728} will be nearly foolproof but at a cost of significant lost power potential.
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
Here is my set-up:
Bottom End = 396ci LT1 motor fully forged (4.030 Bore) 3.875 Stroke, and 5.850" Rods, and 11.1 cr
Top End = GM#867 Pontiac Heads raised runners, 60/40 valve spacing 2.10 intake valves 1.60 exhaust valves, 64cc chambers, 235cc intake ports, heads flow over 330cfm @(.600/.700?) lift. Cam is a solid roller 262/272 @.050"
.424"/.424" Lobe Lift
112 LSA
GM bow tie raised runner intake #10051103
I don't want to buy an 850 carb and then find out that I needed to go a bit bigger. By the way the 995cfm is a king demon with interchangeable venturis which I already have.
Bottom End = 396ci LT1 motor fully forged (4.030 Bore) 3.875 Stroke, and 5.850" Rods, and 11.1 cr
Top End = GM#867 Pontiac Heads raised runners, 60/40 valve spacing 2.10 intake valves 1.60 exhaust valves, 64cc chambers, 235cc intake ports, heads flow over 330cfm @(.600/.700?) lift. Cam is a solid roller 262/272 @.050"
.424"/.424" Lobe Lift
112 LSA
GM bow tie raised runner intake #10051103
I don't want to buy an 850 carb and then find out that I needed to go a bit bigger. By the way the 995cfm is a king demon with interchangeable venturis which I already have.
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[quote="Rick1999"]No you can't!!!!!!!
Sorry it's Friday night and I'm stuck at home, bored More info needed.
hahaha!!!! That's funny, How about some vehicle information what is the weight of your car, how tight are you going to turn the motor, what trans and what stall. Everything that is why I have a 45 question spec sheet on my web sight you have to take all of this into consideration plus sum.
www.devanecarbs.com
Sorry it's Friday night and I'm stuck at home, bored More info needed.
hahaha!!!! That's funny, How about some vehicle information what is the weight of your car, how tight are you going to turn the motor, what trans and what stall. Everything that is why I have a 45 question spec sheet on my web sight you have to take all of this into consideration plus sum.
www.devanecarbs.com
DeVane carburetors are precision assembled and calibrated to YOUR combo. Are you ready for the next level of performance?
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