Will the stock carbs work on these hp500s?
#1
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Ive got 2000 hp 500's, just ported the heads, bumped to cr to 9.1 to 1, changed to a 731 cam, and bumped the rev limit to 5600, trying to prop around 5600.
1st test out we were running too rich, but at 5450 I hit a wall. Do you think i need more carb to get it over 5450? The stock carb is an 800.
1st test out we were running too rich, but at 5450 I hit a wall. Do you think i need more carb to get it over 5450? The stock carb is an 800.
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I think if you want a 502 to make power up to 5600, you need more cam and more carb.
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Patrick
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Carbs might be ok but you need to go to the 741 cams. The 731 isn't much bigger than the stock cam. It's actually smaller than the 500 efi cam.
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Originally Posted by PatriYacht
Carbs might be ok but you need to go to the 741 cams. The 731 isn't much bigger than the stock cam. It's actually smaller than the 500 efi cam.
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Originally Posted by Pat McPherson
I think if you want a 502 to make power up to 5600, you need more cam and more carb.
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Call and speak with Laz at Mesa Balancing...
They get some very big horsepower out of the 800 Holley on 540s.
Great source of info...
Dave
They get some very big horsepower out of the 800 Holley on 540s.
Great source of info...
Dave
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Originally Posted by Griff
I think you are hitting the wall at 5450 because of the cam more so than the carb.
I'd try bigger props; you may be pleasantly surprised.
I have a friend running a 731 in a 454. His boat seems to run fastest propped at 5300-5400rpm.
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I'm running the 741 (on the Dyno right now) with the stock Dart intake and the 800 carb and I am having NO problems with either reversion or the carb.
Sorry HP500's (502's)
Sorry HP500's (502's)
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Damn, sounds like i should have done the 741, I just didnt want to be close to reversion, reliability is what i want with a few more ponies.