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jamis · 05-27-2007, 11:07 AM

It wouldn’t matter if it was roller or not. Rollers are used to reduce friction and you can have steeper lobe ramps to increase duration without increasing lift when changing the profile. A roller with .460 lift would likely have the same spring rating as a flat or mushroom tappet with .460 lift. Ramp speeds and RPM can also have an effect but not as much as total lift.

Be careful if you’re identifying your heads by casting numbers, Casting numbers do not identify what springs came with the head. Only the assembled head part number can ID the spring. Or you have to remove the spring and measure it and its pressure.

Your retainer to seal clearance and coil clearance will limit your lift as well.

Whats a beehive on an engine, I never heard that term before.....I guess I'm showing my age?

05-27-2007, 11:07 AM	#5
jamis F.A.S.T. president Join Date: Sep 2003 Location: Florida Posts: 1,883	Re: stock vortec valve springs? It wouldn’t matter if it was roller or not. Rollers are used to reduce friction and you can have steeper lobe ramps to increase duration without increasing lift when changing the profile. A roller with .460 lift would likely have the same spring rating as a flat or mushroom tappet with .460 lift. Ramp speeds and RPM can also have an effect but not as much as total lift. Be careful if you’re identifying your heads by casting numbers, Casting numbers do not identify what springs came with the head. Only the assembled head part number can ID the spring. Or you have to remove the spring and measure it and its pressure. Your retainer to seal clearance and coil clearance will limit your lift as well. Whats a beehive on an engine, I never heard that term before.....I guess I'm showing my age? __________________ F.A.S.T. President and Founder Fabricators for the Advancement of Sawsall Technology "A fear of the Sawsall is a sign of retarded sexual and emotional maturity." ~Sigmund Freud, "General Introduction to Psychoanalysis" Last edited by jamis; 05-27-2007 at 11:09 AM.