HP500 rebuild...what next?
#11
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The part no. for a mark 4, Gen 5 741 is now 139021. Have to use a cam button in a Gen 6 instead of the retainer plate. Maybe Crane can make one to fit a Gen 6.
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Originally Posted by Blue by You
I almost begged for the 741. Crane told me the 741 is not for Gen 6. That only the 731 would work. I questioned it 3+ times and still received the same answer. Is crane wrong?
http://www.cranecams.com/?show=brows...tType=camshaft
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Steve Gresham
'03 Donzi 33ZX
Steve Gresham
'03 Donzi 33ZX
#13
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Originally Posted by PatriYacht
Go to the Crane 741 cam. The 731 is smaller than some of the HP cams. The new HP 525 cam has the same lobes as a 741 except it is ground with a 114 lsa instead of a 112 lsa.
#14
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Originally Posted by Blue by You
I almost begged for the 741. Crane told me the 741 is not for Gen 6. That only the 731 would work. I questioned it 3+ times and still received the same answer. Is crane wrong?
#16
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The 731 cam has bin replaced with the new Z-camprofile #139011. This cam act like a "bigger" cam caused to the new grind. Powerrange is 1600-5600 RPM and it pulls very strong al way up and idle is smoote 750-800 rpm
#17
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So can I assume that an HP500 with 731 & GIL'S may have less reversion issues than the same set up with a 741? It seems that a lot of reversion discussions are stemming around the 741. Of those who are running 731's vs 741's who's got a bigger reversion problem? And for those experts, in your opinion is the cause of the HP500 reversion issues mainly CAM related or Exhaust related? If you remove the water all together from the tailpipes I guess you'll solve the reversion problem, like cutting the head off a snake, but would a simple "less aggressive" cam change also do the trick?
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Originally Posted by Blue by You
So can I assume that an HP500 with 731 & GIL'S may have less reversion issues than the same set up with a 741? It seems that a lot of reversion discussions are stemming around the 741. Of those who are running 731's vs 741's who's got a bigger reversion problem? And for those experts, in your opinion is the cause of the HP500 reversion issues mainly CAM related or Exhaust related? If you remove the water all together from the tailpipes I guess you'll solve the reversion problem, like cutting the head off a snake, but would a simple "less aggressive" cam change also do the trick?
The 731 isnt much of a performance gain over the stock carb'd hp500 cam, but every little bit adds up.
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Originally Posted by BajaRunner
Bob Lloyd whos opinion I trust and did my engines said the 731 would work with the gils. The 741 would work, but would need to change exhaust. I didnt want to spend the money on the exhaust.
The 731 isn't much of a performance gain over the stock carb'd hp500 cam, but every little bit adds up.
The 731 isn't much of a performance gain over the stock carb'd hp500 cam, but every little bit adds up.
#20
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Originally Posted by Griff
The 800 should be plenty of carb. As for jet sizing, stock jets are not 70's and jetting is staggered. Here are the stock jet sizes.
Pimaries--port-81, starb-75
Secondaries--port-89, starb-93
Pimaries--port-81, starb-75
Secondaries--port-89, starb-93