Ok, in old muscle cars and such they have different cam profiles that are specifically geared to torque or hp. Normally both give u a lil of both but are designed to give more of one than the other. How? What is the difference in the profiles and why doesnt this work in imports?

 

taking a guess:
its prolly the duration of the valve being open vs the ammount it opens

i hope u get what i mean

excuse the crued drawing

 

Im not an expert in the subject.
But I think cams are more optimized mostly for high or low RPM.
low rpm being mostly torque and high rpm being mostly HP.

 

It has to do with a lot of things, that picture above is basically correct.

Depends on when the cam starts to deliver it's mixture, how long it delivers it, and how much it delivers.

All depends on timing, duration, and how big the lobe is.

I think?

 

BAM!! http://www.howstuffworks.com/camshaft.htm

 

changing the profile changes where you make more/less torque. If you set it up to make more torque at higher rpms, the car produces more HP (since HP = (Torque*RPM)/5252 ). The tradeoff however, is that usually that means less torque is made somewhere else (since the cams were optimized for higher rpms), thus you lose low end torque.

 

Honda uses this idea on their engines. They basically put in a cam designed for torque and a cam designed for power, and switch between the two as needed. VTEC.

 

thats the beauty of vtec, u can have low end and good idle, but when u want power up high u can make the secondary lobe as big as you want and u'll get that nice kick of power. u can cam any car out, but it will idle funny as hell and wont be good at low end