[camarozl112]

The camshaft serial number is c1m296

[techinspector1]

Originally Posted by camarozl112

The camshaft serial number is c1m296

SBC, mechanical lifters, 296 degrees advertised duration. This Crane grind might be close.....
http://www.cranecams.com/product/car...detail&p=24417

[69 Camaro SS427]

I bought a GK cam back in the 1970s and only remember some of the details. It was for a Chevy 427 engine.

It was listed as:
Not recommended for street, light chassis with high ram induction
Intake lift: .623 Exhaust lift: .623 Intake duration: 310 Exhaust duration: 330

The problem is I need to change the valve springs and don't know what the spring pressure should be. Anybody have any info on this cam for me? Thanks

[F-BIRD'88]

You jumped on the the tail end of a old old thread.
Next time check the date of the last poster before responding.

This is a general valve spring recomendation for a BBC with a mechanical flat tappet racing cam.

seat pressure 120 to 135PSI open pressure 320 to 390psi.

You need to check and verify your actual installed height and open height pressures and coil bind clearance.

If you never rev this motor that high 7000+rpm you can go to the low end of this scale on seat and open pressure. If you like to rev it up you would want to steer the actual checked spring open and seat pressure up closer to the top end of this scale.
If the springs are now worn out you need to check the cam lobes and lifter feet for wear too. If the cam or lifters is starting to go south at all, replace them as
fresh springs on a bad cam will surely finish it off quick.

The low end of this recomendation scale gives good flat tappet cam life and rpm. The top end of the pressure scale allows more rpm limit
for high rpm competition racing only,
but may shorten the cam lifter service life. There is no free lunch.

[F-BIRD'88]

If you need something more specific than this
call or email Crane Cams Or Isky Cams directly.

Don't be shy, thats what they are there for.
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