GM contact information for camshaft specs?

ss3011 · 07-31-2012, 06:00 PM

The IHRA Rule Book says:

Aftermarket Cams allowed as per horsepower claimed. Must check on or under factory specs for lift, duration, and overlap.

This sounds to me like our old stocker cam specs, back in the 80's. Most of the old cam specs were listed on the Engine Blueprint Sheets along with the checking clearances. Most of that info was removed when NHRA went with the lift only rule.

Mike Taylor 3601 · 08-01-2012, 05:52 PM

That's right IHRA pure stock has got to point to where it is same as pre 1986-87 stocker except for have to have mufflers w/headers they can't be straight thru type have to be baffled,also no additional stroke on crank can't be over stock stroke
Mike Taylor 3601

07-31-2012, 06:00 PM	#1
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 910 Likes: 70 Liked 239 Times in 114 Posts	Re: GM contact information for camshaft specs? The IHRA Rule Book says: Aftermarket Cams allowed as per horsepower claimed. Must check on or under factory specs for lift, duration, and overlap. This sounds to me like our old stocker cam specs, back in the 80's. Most of the old cam specs were listed on the Engine Blueprint Sheets along with the checking clearances. Most of that info was removed when NHRA went with the lift only rule.

08-01-2012, 05:52 PM	#2
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,380 Likes: 371 Liked 319 Times in 108 Posts	Re: GM contact information for camshaft specs? That's right IHRA pure stock has got to point to where it is same as pre 1986-87 stocker except for have to have mufflers w/headers they can't be straight thru type have to be baffled,also no additional stroke on crank can't be over stock stroke Mike Taylor 3601 Last edited by Mike Taylor 3601; 08-01-2012 at 05:54 PM. Reason: addition