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Old 10-31-2012, 12:50 PM
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Here's your cam.....
Saturday Night Special, Part #110691, operating range 3,200 to 6,800 rpm's.
Flat tappet hydraulic, Performance usage, good mid and upper RPM torque
and HP, bracket racing; Street, Heavy, ProET, SuperET,
etc., autotrans w/3500+ converter, oval track; Street
Stock, Enduro, Hobby, etc., 1/4-3/8mile circle track, 10.5:1 to 12.0:1 static
compression ratio advised.
Advertised duration: 294/300
Duration @0.050" tappet lift 238/244
Lobe separation angle 106 degrees

Valve timing @0.050" tappet lift:
Intake opens 17 degrees BTDC
Intake closes 41 degrees ABDC
Exhaust opens 52 degrees BBDC
Exhaust closes 12 degrees ATDC

Intake valve lift with 1.5:1 ratio rocker arms, 0.480"
Exhaust valve lift with 1.5:1 ratio rocker arms, 0.495"

So, to answer your question, would this be too much cam for these heads? The answer is yes. The heads will stall and sign off way before the cam is done pulling. You fellows have to realize that the L31 heads were designed by GM to make the proper hp and torque to haul grandma and the kids to Disneyland, not to do things like bracket racing (description of the cam above). They're great street heads and will flow better than any other PRODUCTION Chevy cast iron head, but they are not miracle heads. Stock valve lift was less than 0.420" with these heads and I'm really surprised that some cam grinder hasn't stepped up with an off-the-shelf hydraulic roller that will work with the stock springs and rail rockers that come on these heads. Like, you could build the motor 9.5:1 SCR and use a cam that closes the intake valve at around 35 degrees ABDC with a very short lift, like around 0.400" and make excellent power on crap gasoline. All you guys seem to think that you need valve lift to the moon, but that's not true on a daily driver. Pull your head out of your kazoo and put down the hot rod magazines.

Last edited by techinspector1; 10-31-2012 at 01:07 PM.
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