Carb comparison article
03-26-2017, 11:51 AM
#1
Carb comparison article
thought I'd share it with you guys.
The test mule, was a 496ci. 4.25x4.31 bore bbc. It had a 12.5:1 compression ratio, AFR 325 heads, 270/282 hydraulic roller with 112 LSA, and .680/.680 lift. 220 seat, 520 open. Crane lifters. Weiand Team G intake. No spacers used.
As you can see, in this test, the 750 CFM, lost everywhere from 4000rpm and up. Less torque, and less hp. By 6000 rpm, it was down 45hp to the dominator, and down 25hp to the 950.
The carbs were new holleys, the ultra HP and ultra dominator.
The test mule, was a 496ci. 4.25x4.31 bore bbc. It had a 12.5:1 compression ratio, AFR 325 heads, 270/282 hydraulic roller with 112 LSA, and .680/.680 lift. 220 seat, 520 open. Crane lifters. Weiand Team G intake. No spacers used.
As you can see, in this test, the 750 CFM, lost everywhere from 4000rpm and up. Less torque, and less hp. By 6000 rpm, it was down 45hp to the dominator, and down 25hp to the 950.
The carbs were new holleys, the ultra HP and ultra dominator.
03-26-2017, 01:32 PM
#2
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I wonder how much difference would be with 10:1 comp and something closer to a 741 cam (Peak 6k). I wouldn't have expected to see that much gains starting at as low as 4K rpm with their combo though. Good info joe.
Based on carb formula at 95% efficiency shows 950 cfm plus so I guess I could see why the big difference based on a 950 carb flows closer to 830 as we know. Regardless here's a true case where bigger is better. Hah
Based on carb formula at 95% efficiency shows 950 cfm plus so I guess I could see why the big difference based on a 950 carb flows closer to 830 as we know. Regardless here's a true case where bigger is better. Hah
Last edited by getrdunn; 03-26-2017 at 01:43 PM.
03-26-2017, 02:38 PM
#3
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Did the Dom use a 4500 intake or use an adapter ?
03-26-2017, 02:42 PM
#5
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Getrdunn - supposedly the Ultra 950's are closer to 950 unlike the old HP950....but I have not seen verification from 3rd parties on this.
03-26-2017, 05:45 PM
#7
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I did just notice their about about 4 jet sizes larger front and rear and no pv in the rear. That's taking the pv into consideration on the holley.
Last edited by getrdunn; 03-26-2017 at 05:55 PM. Reason: Jets
03-26-2017, 10:21 PM
#10
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I recently did exactly that test, a modded dom, stock dom and tim full forces QF 1050 on my dyno on the 548, they were all within a few hp, norms ultra modded 4150 based on a 850 but flowed 1170 kicked all their asses by 15 to 19 hp butthats a work of art!
