balancing the bottom end
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Originally posted by Spyderxl98z24
before integra nem says WHY are cams a factor well cams actually determine your powerband. If you rev it to iunno 8k and then if you rev it to 9k youll see a drop in power due to the cam the cam grind is specific in RPM. if your engine is turning at 9k rpm and your cam highend power is at 8 the cam and valaves cant increase in speed or frequency of the opeing of the valves then you dont get enough air and then you start loosing power or it stays the same. So reving higher doesnt always mean better performance unless you build it to rev that high for a reason. Longer duration cams can rev higher and longer than short duration and hihe lift cams. make since ?
before integra nem says WHY are cams a factor well cams actually determine your powerband. If you rev it to iunno 8k and then if you rev it to 9k youll see a drop in power due to the cam the cam grind is specific in RPM. if your engine is turning at 9k rpm and your cam highend power is at 8 the cam and valaves cant increase in speed or frequency of the opeing of the valves then you dont get enough air and then you start loosing power or it stays the same. So reving higher doesnt always mean better performance unless you build it to rev that high for a reason. Longer duration cams can rev higher and longer than short duration and hihe lift cams. make since ?
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AS far as getting the bottom end to rev high you need the lightest pistons and rods possible all balanced. You need a head with a good volumetric efficiency at high rpms and cams to allow the head to breath. Everything is one big system you need to build everything together in order to make it work on any engine by any manufacturer.
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Don't bother giving me "rep", I won't return it and I think it is stupid.
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Originally posted by na200whp
NO . explain to me how at 8000 rpm the valves on longer turn in sync w/ the crank? if the car stops making power at 8000rpm its not due to the cams inability to open and close fast enough or often enough its because there is not enough air flow to support additional hp.according to your logic adding a bigger cam will in some way help the valves open and close faster even though it will have high lift and longer duration.
NO . explain to me how at 8000 rpm the valves on longer turn in sync w/ the crank? if the car stops making power at 8000rpm its not due to the cams inability to open and close fast enough or often enough its because there is not enough air flow to support additional hp.according to your logic adding a bigger cam will in some way help the valves open and close faster even though it will have high lift and longer duration.
If your cam profile is set to run at 8k rpm and fall off then after that your intake volume isnt sufficiant enough to sustain any higher rpms due to the frequency of the cam duration and how fast the cams open surpase what the engine can consume in air volume. its like takeing short deept bretahs like hyper ventilating sorta. it cant suck anymore air in becuase the frequency is set for lower rpms. Longer duration and a higher lift will be able to open longer at rpm making it possible to increase the intae volume. If you use a stock cam profile at that high of an RPM you just suphocating the engine. so really there is no need to rev higher than what a oem cam is designed for. Understand what im saying ? but usually at that high of an RPM youll just get valave terminal velocity and you start floting valves because a spring cant keep up with the rpms.
