i think this question falls in the advanced catagory. if not im sorry. i bought a cam off ebay. guy said the cam was a lift 630. 630. duration 294. 304. when i got the cam there was no cam card nor any numbers to run on it. cam looks awsome like new. my question is how to i measure the lift and is there any way i can figure out the lobe center my self using a mice? the main thing is the lift. any help would be great. i think its a custom grind. inbetween the lobes is a copper color.

 

If you don't have a lathe (or good way to turn it in a rigid fixture), then get the thing in a block with a crank, degree wheel, timing chain, a head, and #1's valvetrain setup (with checker springs). Put a dial on each valve and write down the degrees at which 0.050", 0.100", and so forth fall. You should get a pretty good idea of what the lobe profiles are like this way, and where they open/close in relation to crankshaft position. With that data in hand, I think there are some good "cam math" websites that can help you.

I am not an engine builder, so there might be some better way.

Checking "lift" only is pretty simple - throw a caliper on the lobes, then multiply by your rocker ratio. On a mystery cam though, this doesn't even get you close to being out of the dark.

 

i might could get access to a collet lathe. not for sure if there is a collet big enough to hold it though the cam looks awsome its a solid roller. i told the guy that i had no proof of what it was, the springs were huge i couldnt run them on my sbc unless i had work done to my heads and the lifters looked cheap and no names on them either ( but he did say the lifters were kind of cheap) what worries me is the cam hasnt ever been run. no sighs of wear no oil no light rust the trash in the bolt holes. but he said he ran it for a while in his drag car.

 

Send it to a cam-shop for a "cam-doctor" and you'll get all the info you need.
It's probably not a cheap process, but it's certainly a price to pay for getting your cam from ebay.

At the very least, you'll have the correct info to sell it later if it's not right for your combo. (and maybe get your money back)

 

X2 on the Cam Dr. It is the only way (I think) to get the actual numbers with out the cam card. good luck.

 

If all you want is the lift spec put it in the motor on the stand. install 1 lifter on the int and exh and use a magnetic base dial indicator. zero the indicator when the lifter is on the base circle. rotate the cam to peak lift. say it's .377 multiply that by your rocker ratio and you'll have a lift number. as a side note I will tell you that if you want the lift number because you are concerned about P to V , you should know that the duration and installed centerline will have a much greater effect. make sure your dial indicator is lined up exactly perpendicular to the lifter or you measurement will be way off. this method is a little crude but it is done every day in 100's of shops around the country.

 

wow thanks everybody ill post some up close pics of it.

 

Where can we send a cam to a cam doctor?? Are there specific shops or do you send to cam manufacturers. Who knows the approx. price?