Help with selecting New Cam Up Compression also

[Bryan Rose]

Well I will be having a comple re-build done this next two weeks and need some help with some componant selections namely a new cam and perhaps new heads if $$$$$ permit.
It is 454 BBC 1975 Gen IV and the application is in a Jet, Wieand High rise with a pair of Holley 660's so if that helps please help me...
Bryan
[ July 21, 2003, 04:33 PM: Message edited by: Bryan Rose ]

[HBjet]

What heads do you have on it now?
HBjet

[Bryan Rose]

Oval Combustion chamber heads I believe is what the casting # gave me...
Bryan

[Bryan Rose]

Ny help on the Cam selection here. I was looking in the Comp cams book and found an Aplication for Jet Boat " Performance with A Imp."
Turns out my stuck exhaust valve was a wiped lobe instead. But while it is out I am thinking of upping compression to about 10.00 -1 any ideas on this , want to still fumn 93 pump gas in it. Is upping the compression a good idea here?

[Bryan Rose]

Ny help on the Cam selection here. I was looking in the Comp cams book and found an Aplication for Jet Boat " Performance with A Imp."
Turns out my stuck exhaust valve was a wiped lobe instead. But while it is out I am thinking of upping compression to about 10.00 -1 any ideas on this , want to still fumn 93 pump gas in it. Is upping the compression a good idea here?

[Dennis Moore]

With the dual four barrels I would keep the camshaft duration a little on the conservative side. I wouldn't go any more than 225/230 intake/exhaust duration and around .520 - .540 lift with 110 to 112 lobe centerlines. Wet headers are a little rough on water reversion so use the 112 centerlines with them, 110 with exhaust manifolds.
If you raise the compression, (a good idea) use a piston with a dome that reaches all the way across the combustion chamber (open chamber piston). You will increase the compression without the tall dome of a closed chamber piston. Use a 9.5:1 piston.
Deck your block so the flat part of the piston comes to within .040 inches of the flat portion of the cylinder head (with head gasket installed). This will give you maximum quench and lower your octane requirements.
Install 2.19 inch diameter intake and 1.88 inch diameter exhaust valves into your stock heads.
You will have a nice engine!
Sincerely
Dennis Moore

[Bryan Rose]

Hey Dennis , I was just beginning to think no one here knew anything about Cams pistons etc... thanks and check your P.M.'s