Cam King

[Orr89rocz]

Mike,
I recall talk of a cam program in progress that would eventually be available for purchase. Is that still in the works?
Thank you.

No. We use to sell a cam program I wrote, that calculated the optimum cam, and picked the closest lobe profiles, from all our designs.
I did this, to reduce the amount of time, I would spend on figuring out what cams my customers needed. It turned out to be the opposite. The program would pick the same profiles, I would most likely pick, but the customers would either not believe the results, or have 20 questions on why the program picked the profiles. I spent more time answering questions, then I would spend calculating what they would need for a cam.

Lol customers know cams better than the cam guy apparently lol. Thats my favorite when a guy gets a recommendation and it doesnt look like what they think it should based on what they have read and seen on the net lol

[skinny z]

It gets even more complicated when 3 cam guys offer 3 different specs and they're all different from what the web or books or magazines throw out there.
That problem is that ultimately the cam selection process has to go beyond filling out a form. There's a conversation that has to happen if you want to have something really dialed in.
Either that or you take the recommendations and decipher them the best you can for whatever it is you intend to do. Some understanding of the science is helpful.
I'll say though that for the most part, that being the average enthusiast and not the professional, the performance results might differ so little that the cam spec can move one way or another with little noticeable effect. (All to a certain degree of course). There would be too many other variables to be able to isolate the cams influence on the entire package.

Anyway, that's my 2 cents.

[learner1]

Mike,

You've said that it's ok to keep raising lift even though the port flow stops increasing as long as the port doesn't go turbulent.
Lets say that after .500 lift the port doesn't go turbulent but the cfm starts dropping. How much of a cfm drop does it take before you stop adding lift to the lobe?

[williamsmotowerx]

Mike,

You've said that it's ok to keep raising lift even though the port flow stops increasing as long as the port doesn't go turbulent.
Lets say that after .500 lift the port doesn't go turbulent but the cfm starts dropping. How much of a cfm drop does it take before you stop adding lift to the lobe?

The answer there is mainly how stable is your valve train, how long you expect the motor to last. Cam gets aggressive, and motor gets expensive. The port and fill can "usually" tolerate going up on lift... but you'll usually want to RPM it quite a bit more to take any advantage of the extra lift.

[Mummert]

The first thing you should look at, is what is the MCSA for a certain engine at a certain RPM. Wallace racing has some good calculators. The numbers always look smaller than you think it should be. But figure that out first. Then you will have to look at your head and see where you can get close to that area. As far as speed goes if you can achieve 320-340 average fps velocity in that region "it'll run".
Most big blocks the MCSA will be at the throat as they are valve limited engines, small blocks will usually be somewhere between the pushrod and the shortturn, and have more valve area and curtain area per cubic inch than big blocks. Because of this they do not need as much duration, lift, etc. to be as efficient. 4 valve stuff even more so.