Another Cam Selection Thread

[OneBad93Z]

I have finally gotten around to pulling my stock heads off and am putting the AFR 165's on that I've had for far too long, so now it's time to look for my cam. I want to do this right the first time, so I'm looking to go custom, but after calling up a few Cam company's I've been told an off the shelf cam would be fine for me, as with my stock compression ratio a custom cam wouldn't yield enough results to justify the money.

Crane Cams has a cam that seems decent for my combo, I have SVO 1.72 RR's and this cam was designed for cars with 1.7's. It's the Powermax 2031 cam

.519/214* Intake
.534/220* Exhaust
Not sure what the ICL is

The duration seems kind of low, but I have to constantly remind myself that bigger is not necessarily always better. These 1.72's sure were great with the stock Heads/Cam, but now that I'm looking for a decent cam they are more of a hinderance unless I go custom, I constantly have to consider PTV clearance. I don't really want to buy some 1.6's, does anybody have a good recommended OTS cam for my combo? I'd like to hear some real world experience and some good theory if anybody has some. I'm going to call AFM and Comp tomorrow and see what they have to say. I really like the price of an OTS cam, but I want to squeeze all the power out of this combo that I can, since I'm a bang for the buck kind of guy

 

[Michael Yount]

The reason for going with a custom has nothing to do with your set up - high compression, low compression, big heads, small heads, etc. The reason for going with a custom is so you have more certainty that the cam you install is actually going to accomplish what you want to accomplish. Most of the cam companies out there are going to try and sell you an off the shelf grind - it's what they do. They already have them in stock and they'd like to try and move them.

If you have clear goals that you're trying to accomplish with the motor, and you know the rest of the components you're gonna be using, letting one of the reputable cam designers model your set up is the surest way to have some certainty that when you fire that new combo up the first time, it's gonna run the way you expect it to - make the power level you were expecting in the rpm range you were expecting.

Right off the bat I can tell you that the 2031's split duration (more exhaust than intake) is designed for a head that is intake biased in it's flow capabilities. A head that doesn't flow as well on the exhaust side relative to the intake side can benefit from a cam that has more exhaust duration and/or lift to make up for the head's flow characteristics. The 165's aren't saddled with that issue - they flow quite well on the exhaust side. Most of the specs on custom grinds that are put together for the 165's are much closer in duration for intake and exhaust. I'd stick with your original plan - let one of the custom guys help you figure it out. Otherwise, you're just guessing.

 

[5spd GT]

And that is why I went with an FTI cam...going to install in 2 1/2 weeks...can't wait...