Help, what carb would you pick?
#13
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If the price is right, would you be interested in selling your BG 750? Only need one
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#14
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Originally Posted by Whiteknuckle
Cord
The Holley Tech guy on their help line told me a rule of thumb is about 15% additional CFM required for Marine applications when using the formula that Rookie mentioned. From what I have seen on the dyno, that makes sense.
The Holley Tech guy on their help line told me a rule of thumb is about 15% additional CFM required for Marine applications when using the formula that Rookie mentioned. From what I have seen on the dyno, that makes sense.
Finally, got somebody to confirm my theory. Thanks!
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So that means that my new carb is to small
I just bought a Edelbrock 750cfm for my (454*5100/3456)x1.15=770cfm...
An 800 would probably be more appropriate then
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I just bought a Edelbrock 750cfm for my (454*5100/3456)x1.15=770cfm...
An 800 would probably be more appropriate then
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One point missed on the formula, you do not have a 100% efficient engine. You missed was deducting the efficiency factor. The average engine is less than 90%. Even top Nascar engine builders can not get 100%.
454 x 5300 / 3456 x 90%= 626. I always moved up some as did Cord. Any move up here is a guess. I would use a 750 Holley Double pump. 626 x 1.15=720.
454 x 5300 / 3456 x 90%= 626. I always moved up some as did Cord. Any move up here is a guess. I would use a 750 Holley Double pump. 626 x 1.15=720.
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Originally Posted by Linster
One point missed on the formula, you do not have a 100% efficient engine. You missed was deducting the efficiency factor. The average engine is less than 90%. Even top Nascar engine builders can not get 100%.
454 x 5300 / 3456 x 90%= 626. I always moved up some as did Cord. Any move up here is a guess. I would use a 750 Holley Double pump. 626 x 1.15=720.
454 x 5300 / 3456 x 90%= 626. I always moved up some as did Cord. Any move up here is a guess. I would use a 750 Holley Double pump. 626 x 1.15=720.
Thats right! Then I'm still ok with my 750...
#18
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Im spinning mine at 5400 with a 780 and a single plane and the vacuum is near zero. Ive always been led to believe that if you undersize the carb the wot vacuum reading will be higher.