Is there anyway to measure duration on a cam that us already installed in a car?

 

Yes, get a degree wheel (and kit). You will have to yank the water pump, crank pulley, driver side valve cover. I am not sure about the timing-chain cover... I think that is all... You can download the instructions from CompCams web site...

OR

https://ls1tech.com/forums/generation-iii-internal-engine/327734-cam-guide.html

Start with post #10

 

nope - you would have to bring it to a shop that can cam doctor it, unless you have the serial number - then you can call the manufacturer and find out the specs