Cam Specs and reversion
03-03-2016, 04:36 PM
#11
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I agree it's not a big cam for a 540, and should be able to hit the 6000rpm peak power range no problem. In my thinking, it is a bit bigger then you need for 800hp. Also, looking at the whole combo; 800hp at 6000rpm will be around 6 pounds of boost. 6 pounds of boost at 6000rpm with the vortec will be about 2lbs of boost at 3200rpm. So, when you mash the throttle, acceleration wont be as good as it would be if you had 8 pounds of boost and 800hp at 5500rpm. Also, a prop for 6000rpm on a single engine Cat with a deep drive takes a fair bit of jam to get out of the hole when the boat is loaded. I'm not saying it wont work, I'm sure it will run great. Just adding input from similar combos I've actually built.
03-03-2016, 04:52 PM
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03-03-2016, 05:03 PM
#14
Like everyone else 800 was going to be enough, then a 1000 was going to be way to much, then M4 with 15psi. Your probably right the 256/264 is too big for 800, we didn't care, with the EFI it idled well enough to shift in and out of gear, pulled skiers and ran in the 130s. I think the cam he has is fine for what he wants to do.
03-03-2016, 05:06 PM
#15
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The supercharger and intercooler are from a 502 MPI kit that I have been running for a number of years with great results. When I started the project I was planning to use Holley EFI and blow through the Holley Throttle body. I have just recently decided to use and modify an MPI to work on the 540.
03-03-2016, 05:13 PM
#16
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The cam listed by the op would be good choice with Gill exhaust and a hair drier. Those blowers don't start making power til past 4000rpm. The smaller cam will idle better and make decent midrange torque.
03-03-2016, 05:13 PM
#17
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The supercharger and intercooler are from a 502 MPI kit that I have been running for a number of years with great results. When I started the project I was planning to use Holley EFI and blow through the Holley Throttle body. I have just recently decided to use and modify an MPI to work on the 540.
03-03-2016, 05:15 PM
#18
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I agree it's not a big cam for a 540, and should be able to hit the 6000rpm peak power range no problem. In my thinking, it is a bit bigger then you need for 800hp. Also, looking at the whole combo; 800hp at 6000rpm will be around 6 pounds of boost. 6 pounds of boost at 6000rpm with the vortec will be about 2lbs of boost at 3200rpm. So, when you mash the throttle, acceleration wont be as good as it would be if you had 8 pounds of boost and 800hp at 5500rpm. Also, a prop for 6000rpm on a single engine Cat with a deep drive takes a fair bit of jam to get out of the hole when the boat is loaded. I'm not saying it wont work, I'm sure it will run great. Just adding input from similar combos I've actually built.
03-03-2016, 05:22 PM
#19
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That thing will be a beast with the new combo. Is it a V4? You may be better changing gear ratio so prop selection is a little easier. Some of the bigger pitch single stuff can be finicky to dial in.
03-03-2016, 05:30 PM
#20
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The tag on the blower says V4J race M. With the extra 600 rpms over what I have now I may be as fast as I need or dare to go.
