View Full Version : Cam speed
cervidog
12-02-2013, 03:15 AM
The cam turns at half the speed crank in a sbc does it not?I am going to take the cam I have put it in some V blocks,use some indicators,and try to map this thing so I can try to match that info to the cams being recommended to me.
roadkill2
12-02-2013, 05:38 AM
Why not just discern what kind of cam you have from it's specs available on the manufacturer's web site?
Certainly be a lot simpler . .
Of course, that's assuming you know who made it . . . And I'd start by finding that out . . .
cervidog
12-03-2013, 03:07 AM
When I called comp cams with numbers on cam they said they didn`t have that # in there catalog? I am not sure if the cam is so old or if it is a knock off or what.
roadkill2
12-03-2013, 06:35 AM
Dunno. Were it mine, and it was doing the job, I wouldn't worry about it.
If you want to change "Up" then it doesn't matter what it is, you need to talk to a camshaft salesman/technician and see where the next step might be.
That's my take on it, but some of those up here may offer you other advice that's just as good or better!
oldandtired
12-03-2013, 07:31 AM
[quote="roadkill2"]Dunno. Were it mine, and it was doing the job, I wouldn't worry about it.quote]
x 2
It takes a lot of time to degree in a cam. Throw the biggest degree wheel you have on the crank hub. Now, measure the intake duration at zero, .050, (.100 and .200 if you are into lobe intensity) and full lift. Then you do the exaust side. Calculate centerlines and lobe separtaion angles. Throw a mock up head on these and measure push rod length.
OK we are thru, right? For 98% of us, that is it.
Think about this. We have only measured 12-1/2 percent of the available data.
Any one have a cammaster?
roadkill2
12-03-2013, 03:16 PM
Heh, heh, the problem with that is . . I've seen three guys do this on the same camshaft and come up with three different sets of measurements . .
But, that will tell you pretty much what you want to know if you do it three times and get the same answer at least twice . .
Theoretically, you don't/won't need the V blocks because you have an engine . . the engine is better . . .
cervidog
12-04-2013, 05:37 AM
Time I got,money I don't.I am just trying to get the best info I can.If I end up with no more cam than I had that would be fine,I don't want less.i also don't want to mess up my expensive cam bearings.hindsight should have done this with old bearings befor I pulled them.