richierich14608

So in terms of horse power, does a cam's duration or lift determine how much power a cam can build? Does a cam with a lot of lift make hp, or does a cam with a lot of duration make more power? For instance, lets take two popular cam choices: the 212/218 and the 224/224. If these two cams with the same lift of lets say .550 were to run in a 5.3, which would make more overall peak hp?

viciousknid

iTrader: (8)

Feel free to call me out, but it's my understanding that the LIFT is whats going to determine how much air/fuel is flowing through the chamber. More air and fuel is more HP.
The Duration of the cam is going to determine where the HP/TQ is placed
A lower duration cam will have more low end power than a high duration cam.

Your going to build more power as you raise your rpm's so in all actuality they go hand in hand in producing power.

As i said, that's my understanding. someone will chime in with more specifics and correct me.

sonoma43

iTrader: (1)

That sounds about right to me also. You just have to know the limit for the application to make the right choice! Just remember bigger is not always better.

artypyro

iTrader: (4)

also, more duration= more time to get the air/fuel past the valve

I say decide on duration based on where ya want to make power and get as much lift as ya can

InchUp

iTrader: (2)

It's not about peak horsepower. It's the area under the curve that matters most. If motor "A" has less peak power than motor "B", but motor "A" has more area under the curve, motor "A" will be faster, all things equal.

I'd go with the 212/218.

closet red neck

iTrader: (6)

If it was me, get a cam with more duration(keeps the valve open longer), less stress on the valve springs and net more hp on the big end if thats what you're after.

James

closet red neck

iTrader: (6)

Very well said.........

James

richierich14608

So can someone explain to me then what "area under the curve" means exactly.

InchUp

iTrader: (2)

Best article I could find for you short of opening up my Calc II math book.
http://www.sportcompactcarweb.com/ed...ble/index.html