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Old 04-02-2008, 08:33 PM
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Originally Posted by 1967chevelle454
So do you guys think I could get away with 10:1 with this cam and pump gas?
If its just 10:1 and not over and you build the motor with proper piston-head quench clearance and use a cooler than stock heat range hi perf spark plug and get the carb jetting and timing just right you should be ok. May have to take a few degrees of spark timing out for street use.

Hi Perf Big Block Chevys work a lot, lot better with a mechanical lifter camshaft.

Here are two better/nicer/sweeter street/strip Magnum solid series cams for your 454.

Comp cams #11-219-4 294S solid Magnum camshaft.

And Comp cams #11-551-5 CB-280S-10 "Magnum Muscle" solid camshaft.
Either, works very well in the type of motor you are building.
( this is the "LS-6 cam on steroids!") A nice S&S cam.

For a +.030" 454 BBC with 10:1 cr use this TRW/Speedpro L2349F-30
combined with a "0 decked block" and open your heads up for a 123CC combustion chamber (deshroud for big valves) 10.09:1 finished cr.

Or you can use this other smaller domed piston #L2399F-30

combined with a "0 decked block" and mill your heads to 110CC chamber volume for 9.93:1 finished cr.

If you don't want to "0 deck the block" then use the factory GM LS-6 .022" head gasket (GM parts dealer item) and just cut .005" off the block decks to clean them up.
Your effective measured cr and net quench clearance will be the same as above.
Can be done either way.

The secret is getting the combustion chamber volume, piston deck clearance ( deck height) and piston dome volume matched up to get you 10:1 even and .040" net piston-head quench clearance.

if you don;t bother to get it right, don't expect it to run on 93 octane gas.

Last edited by F-BIRD'88; 04-02-2008 at 08:59 PM.
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