Calculating valve overlap?
07-30-2009, 10:48 AM
#1
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Calculating valve overlap? okay ive been researching this but cant really find a definate answer.
ive got all the specs i need on the cam card.
okay, lots of guys talk about a cams overlap using durations at .050, instead of the cam duration at initial opening and closing points. ive read that you need to have that info do accurately figure overlap.
lemme know what your guys formulas are...
my cam duration at .006" is 271/280 on a 112lsa ( lobe center lines are 109int and 115exh)
thanks,
Jeremy
ive got all the specs i need on the cam card.
okay, lots of guys talk about a cams overlap using durations at .050, instead of the cam duration at initial opening and closing points. ive read that you need to have that info do accurately figure overlap.
lemme know what your guys formulas are...
my cam duration at .006" is 271/280 on a 112lsa ( lobe center lines are 109int and 115exh)
thanks,
Jeremy
07-30-2009, 11:07 AM
#2
Overlap at .006" is calculated the same as at .050" and .200"....just use the durations and LSA at that lift.
(Intake Duration + Exhaust Duration)/2 - (LSA*2)
(Intake Duration + Exhaust Duration)/2 - (LSA*2)
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07-30-2009, 06:51 PM
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My 228R on a 112 LSA has 4* overlap @ .050 and 53* @ .006.
When talking overlap of a cam i assume its the 53* that would be mentioned?
Cheers Mike.
07-31-2009, 09:29 AM
#4
More often than not, when people refer to overlap on the forums they are speaking of the .050" numbers.
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POWERBOND - ASP - AND MORE!
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COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
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