Is that in response to my post?racerbox77 said:You match the cam to the head flow numbers.
Is that in response to my post?racerbox77 said:You match the cam to the head flow numbers.
9 deuce gt said:LEE93COBRA:
This is exactly where I had hoped this thread would go. To answer your question about the cam, my answer is....I don't know. LOL. You aksed the question exactly the way I couldn't get it out originally. Is there more performance to be had out of the AFR 165's? On other boards I have asked this question, and the answer I get is that the heads flow ~250 cfm. Use the Cobra intake, ported to flow ~250 cfm, and pick a cam that offers low end torque, usually with ~ .500 lift. This is supposed to be the street setup to have. (obviously you want a more track oriented combo) But my question here is where do you draw the line. Can you run a track, high RPM setup on the street and be happy. Is there going to be too much of a trade off for low end punch? Is it all in the gearing? How can you get all of the potential out of these heads. There is a lot of hype surrounding these heads, so why not try to wring out the power?
Here is how I see it, right or wrong. The heads flow ~250 cfm at .500 and continue on to .600 lift. If the intake can support this, why wouldn't you get a cam that is making it's power at .500 lift? Would the setup be radically different if the cam was supporting max lift at .600? How would that feel on the street with the right supporting cast? On another note, what IS the right supporting cast? Do you neccesarily need to have better flowing components at .600 lift? Would the intake have to be hogged out? Would the 75mm T/B be needed, or would the 65mm T/B support enough flow to get the desired times? These are questions I do not know the answers too.
LEE93COBRA said:Here is what AFR claims http://www.airflowresearch.com/165sbf_sh.php
I'll agree that heads is where its at but you got to have cubic displacement to justify having a big head
9 deuce gt said:believe what you are saying, is that having a cam with just .500 lift will give you great low end torque, but will be out of gas early in the RPM band. Having more lift will raise the RPM band, but get you into the sweet spot of the heads flow when the gearing is correct. Is this the way to maximize potential of these heads?
cobra93 said:This really isn't the case, guys. At these power levels, and these head flow numbers, lift is not nearly as big a player as duration. A good example of this is the three Anderson cams at the following link: http://www.andersonfordmotorsport.com/dynojet/50-cams.html#hi-rev
Lift is the same, but duration is increased with each step up in cam. See how the max achievable rpm is driven by duration? Another example is the NMRA Pure Street cam. Max lift is 0.500" with no limit on duration.