100 Cams

[Michael Oritt]

I have two 100 cams that I dug out of a storage bin.

Measuring the lobes on the first one I get the following profile (starting with Exhaust Valve #1 and proceeding back):

Exhaust 1: 1.375
Intake 1: 1.404
Intake 2: 1.384
Exhaust 2: 1.387
Exhaust 3: 1.328
Intake 3: 1.399
Intake 4: 1.391
Exhaust 4: 1.364


Measuring the lobes on the second one I get the following profile:

Exhaust 1: 1.451
Intake 1: 1.440
Intake 2: 1.443
Exhaust 2: 1.451
Exhaust 3: 1.445
Intake 3: 1.426
Intake 4: 1.441
Exhaust 4: 1.429

Can either of these cams be reground? FWIW the second one was an Iskenderian Cam (I think a T-3) put in by the original owner. The first one was the stock cam that he replaced with the Isky.

All opinions appreciated.

 

[GregW]

Hi Michael,
That depends on a couple things. The best option would be to take it to a cam regrinder and ask them. I'm guessing that the measurements you are giving are from the heel to the toe of the lobe (the long measurement). Even though those numbers are different, it doesn't mean the cam is worn. You need to subtract the base circle measurement for each lobe (perpendicular to the heel/toe) to get the lift of the cam. You may find that the 4 intake and 4 exhaust will be closer to each other then. This won't be the total lift because it doesn't take into account the ratio of the rocker or the valve lash. If you do need to bring them back into spec, you don't want to remove so much material from the base circle that it is flush with the shaft itself. The wilder the cam grind on a regrind, the more material they will need to take off the base circle to create a larger difference between the base and the heel/nose dimensions. If you want to change the lobe centers from what they are now, you won't be able to grind as much off without welding more material on, then grinding that off.

 

[Michael Oritt]

Greg--

I really don't want to have them reground--I simply want to clear them out without chucking them in the garbage. Do you have any opinion what they might be worth as is on ebay?

 

[GregW]

Honestly I don't know a figure. New cams with an M type grind are going for 395ish GBP. If you do try to sell them, I'd recommend doing the math to find out how close the lobes are to each other. If they're good, you should fetch a better price for them. I have an old Isky catalog and it doesn't list a grind for the 100, so I'm not sure what the specs of your second cam are. Maybe give Ron (Ed's son) a call. I have their T-3-6 grind in my 3000. It has a 268° duration, but that may not have any bearing on anything.

 

[glemon]

Well if the choice is simply pitch or E-bay why not list them for a low price and see what they bring, more times than not when I have had trouble selling something when I list it starting at or close to what I feel is a reasonable value and it doesn't sell, then start it at a ridiculously low bid I end up selling it for a final price of more than the starting bid the first time around, maybe people like the look of a bargain then keep bidding.

Good Luck!