How to tell an original 340 cam from repro?

Posted By: ragtop

How to tell an original 340 cam from repro? - 01/15/10 02:27 PM

I have a cam that I took out of my 1971 Challenger 340. I measured the lift at valve before I removed it, and it was right at spec, at .429/.444. So this cam is eather an original or repro. The only I.D. on this cam is as follows.

1) Between the first journal and the first lobe, there is some green paint and two sets of numbers.
One set is raised and is 1138. The other is embedded and says 1136.

2)Between the last journal and the distributor gear are two embedded numbers. One says D1 and the other says C1

Can anyone tell the difference between the original and repro? Thanks.

Posted By: ragtop

Re: How to tell an original 340 cam from repro? - 01/16/10 12:33 AM

Anyone? Thanks.

Posted By: I go fast

Re: How to tell an original 340 cam from repro? - 01/16/10 02:39 AM

Quote:

Anyone? Thanks.

What difference would it make?

Posted By: dave571

Re: How to tell an original 340 cam from repro? - 01/16/10 03:29 AM

Does it matter?

Besides that, a cam grinder will tell you that unless you have the lifters that were used on it before, in the right order, it's garbage now. New lifters will wipe the lobes off.

Also, due to differences in lifter bore align etc, it really only should be used in the 340 it came out of, even if you still had the lifters in the right order..

In the old days(when oil was still decent) you could get away with a lot in the area of cam swap. These days, it goes to heck in a hurry.