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rcoon 09-19-2007 08:24 PM

454 rebuild question
 
Not looking for anything insane but want a more HP 400-450 range.

Had it rebuilt last year and a valve head broke off so back to the drawing bore.

I have a holley 950 mpi fuel injection, CMI sport lite headers, comp cam mild 262 xm etreme, stock crank and rods. seal power forged pistons 9.5:1 compression.

engine is a bore .030 atm with 781 big oval heads. I am considering the 496 option.

Any suggestion on what parts and what brand to use. the heads I am thinking manley extreme duty series. because i don't want valves breaking again. Crank bearing going with the clevite

Not a real motor head just want to have fun in my 2550 sx chaparal boat.

Matt-Sthlm 09-20-2007 01:08 PM

Hi there.

I talked to Competetion products yesterday about htis.
Give the a call and discouse it.

The 496 option.
He told me that the 781 or 049īs will stop to work over 6000rpm on a stroker.

DMOORE 09-20-2007 01:21 PM

The 454-to-496 option is a great way to go with a boat. Torque is king, and the extra cubes will make a big difference. The heads you have are fine, just have them cleaned up a bit when you rebuild them. Remember use the torque, there is no need to spin that motor to 6000 RPM's. Prop the boat to 5400 max and it will live a very long life. Use good ARP fasteners and a cam that will give a big flat torque curve and enjoy. I've known a few people that have gone this route, and they could not be happier.




Darrell.

rcoon 09-20-2007 05:02 PM

Thanks I talk to comp cams tech help. alot of info seems i need to get a cam for more flow

My current cam setup puts my rpm at 5k max. I like it to stay at 4800. It I get setup correctly how long can I run my engine at 4500+ RPM's

Quick verfication on fuel mixture. I beleive I should be at 11.8 to 12.2. Plan on putting a wide band O2 sensor so I know exact fuel mixture

What Manley valves do I use extreme or severe duty SS? Who's 496 kit should I use? Eagle, World?

for the Main bearing do I use the clevite H or p series?


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