cam timing ?

Aubrey N Bruneau · 07-04-2010, 12:03 PM

No doubt, Greg... in our Stock class, moving the cam around, in order to achieve clearance, is all too often the case. Makes it even more crucial to degree in your cam, check clearances. I run mine 4 degrees retarded. My exhaust lobe is not the excessively violent action ( minimized seat timing ) compared to that of my intake lobe, so that, combined with the lighter exhaust valve, makes it easier to control. I have my valves "sunk" approx .050" deeper than spec ( creates somewhat larger head comb chamber cc's ), in order to achieve my whopping .035" piston-to-valve clearance on the exhaust. Intake is at around .070", so it's fine. Why insist on retarded ( maybe it comes naturally ? ) ?
I just couldn't ignore the 22+ HP and 200-300 RPM increase on the dyno.

07-04-2010, 12:03 PM	#7
Aubrey N Bruneau Member Join Date: Sep 2003 Location: South Eastern Alberta, Canada Posts: 311 Likes: 6 Liked 7 Times in 3 Posts	Re: cam timing ? No doubt, Greg... in our Stock class, moving the cam around, in order to achieve clearance, is all too often the case. Makes it even more crucial to degree in your cam, check clearances. I run mine 4 degrees retarded. My exhaust lobe is not the excessively violent action ( minimized seat timing ) compared to that of my intake lobe, so that, combined with the lighter exhaust valve, makes it easier to control. I have my valves "sunk" approx .050" deeper than spec ( creates somewhat larger head comb chamber cc's ), in order to achieve my whopping .035" piston-to-valve clearance on the exhaust. Intake is at around .070", so it's fine. Why insist on retarded ( maybe it comes naturally ? ) ? I just couldn't ignore the 22+ HP and 200-300 RPM increase on the dyno. __________________ Aubrey N Bruneau 6409 C/S 62 BelAir sport coupe, 409 HP 409