how much Horsepower?
#11
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checked plugs NGKUR4 after Speed run at 5000 rpm.
Plugs were white The dominators have 86 front 90 rear in jet size will fatten up to 90 front 94 rear and try again.
Fuel systems is as follows 2- 1/2 lines drawing from the main tank
# 8 running to fuel seperators then # 8 runs too mechanical holleys mounted on each engine. Then it is backed by Two Comp
140 gph electrics teeing with the output of the mechanicals.
Gas pressure on the Gaffrigs sits at 7psi at all speeds.
Plugs were white The dominators have 86 front 90 rear in jet size will fatten up to 90 front 94 rear and try again.
Fuel systems is as follows 2- 1/2 lines drawing from the main tank
# 8 running to fuel seperators then # 8 runs too mechanical holleys mounted on each engine. Then it is backed by Two Comp
140 gph electrics teeing with the output of the mechanicals.
Gas pressure on the Gaffrigs sits at 7psi at all speeds.
#12
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thats not where rpms are !!
its going away where it should with that cam !!
your chasing shadows until you listen to this stuff ,that cam is a common 502 cam and slighty small for it
fuel pressure is fine !!1mixture could be lean but really thats not it
its going away where it should with that cam !!
your chasing shadows until you listen to this stuff ,that cam is a common 502 cam and slighty small for it
fuel pressure is fine !!1mixture could be lean but really thats not it
Last edited by bobby daniels; 05-28-2003 at 03:19 PM.
#13
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I think this was the best run at 89mph notice how much lower the rooster is.
#14
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Originally posted by bobby daniels
thats not where rpms are !!
its going away where it should with that cam !!
your chasing shadows until you listen to this stuff ,that cam is a common 502 cam and slighty small for it
fuel pressure is fine !!1mixture could be lean but really thats not it
thats not where rpms are !!
its going away where it should with that cam !!
your chasing shadows until you listen to this stuff ,that cam is a common 502 cam and slighty small for it
fuel pressure is fine !!1mixture could be lean but really thats not it
#15
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http://cranecams.com/master/apps/chevy52.htm#3. Hydraulic Roller
this is the site where i got the info on the cam thats in it
this is the site where i got the info on the cam thats in it
#16
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I give up ,no roostertail no power ,it can't carry the boat no h.p.
you should have called this thread look at my boat run
AS I said I know that cam well WE'VE used alot of them it is most likly the most used cam on this board !!!!!!!
I would go to a solid roller and something in the 242/252*duration at .50 and 680 lift on a 112 lobe center then it will run also the heads need to really have a good port job ,and double check the compression it should fly
you should have called this thread look at my boat run
AS I said I know that cam well WE'VE used alot of them it is most likly the most used cam on this board !!!!!!!
I would go to a solid roller and something in the 242/252*duration at .50 and 680 lift on a 112 lobe center then it will run also the heads need to really have a good port job ,and double check the compression it should fly
#17
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Caveman, check www.cranecams.com Crane says that cam is intended for 454-502 motors with a power range of 2500- 6000 rpms. bobbies daniels is right, that cam is too small.
#19
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These guys are right. Not enough cam to pull 6000 RPM. I would even go bigger than the one that Bobby recommended. Ultra Dyne has a low compression solid roller for 502-540 pleasure boat motors. The duration is 264/270 @.050 with .670" lift on a 110. That is only my opinion.
#20
arneson-industries.com
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Do you have trim indicators and do they work? Do you know where the neutral trim position is?
Your rooster tail is a function of propeller rpms and trim angle, not speed.
The faster you go the lower (not shorter) the rooster tail should be.
You need to run the boat with the diameter cut down before you go messing with anything else. Otherwise you are chasing too many changes at once.
Who cut the propellers down? You should have used Hale Propellers in Ct. for this as they have experience with surface propellers.
You should be able to gain at least 500 rpm from chopping 1" diameter off the propellers. If there is no change, then you should start looking elsewhere for rpms and speed.
Your rooster tail is a function of propeller rpms and trim angle, not speed.
The faster you go the lower (not shorter) the rooster tail should be.
You need to run the boat with the diameter cut down before you go messing with anything else. Otherwise you are chasing too many changes at once.
Who cut the propellers down? You should have used Hale Propellers in Ct. for this as they have experience with surface propellers.
You should be able to gain at least 500 rpm from chopping 1" diameter off the propellers. If there is no change, then you should start looking elsewhere for rpms and speed.