lower90xcab

iTrader: (2)

Is anyone grinding cams from billet steel or are all the aftermarket cams cast steel?

My motor mods will be port matched heads and intake, 1.6 cc pro mag rollers, #918 springs, shorty headers, Tremec TKO 600 5spd, either 2.5 or 3inch exhaust and h-pipe, built/narrowed 12bolt with 4.11gears and posi.

I think that my CC306 that I just ordered isnt going to work the way I would like with the mods I have. So Im thinking about going to a custom grind. What are your guys thoughts on this topic?


Thanks
Lower90

seawolf06

iTrader: (8)

My old cam was billet from Cam Motion, but I don't understand how that makes any difference on a HR.

1997bird

iTrader: (2)

All roller cams are made from billet steel. The two piece design (so that you can use a steel distributor gear) HR cam for our LT1's is made from a S.A.D.I billet steel. Most all of your SR cams are made from a Alloy Steel Billet. Your flat tappet hyd & solid cams are made from a Proferal Billet steel.

seawolf06

iTrader: (8)

Do you know the number codes for the differences? (i.e. 4130 = chromemoly)

1997bird

iTrader: (2)

That I do not know. I can find out the next time I talk with my cam grinder.

Old SStroker

Not necessarily.

For a custom LT1 cam you could specify cast ron or billet steel. The steel alloys might be case hardened 8620 or induction hardened 5150.

BTW, what is S.A.D.I steel? AFAIK, "SADI" was a B-52 bomber upgrade.

Proferal is a cast iron used for cams.

seawolf06

iTrader: (8)

8650 Induction Hardened Core is what my card says. Only thing I can find on Google is 8650 = Chrome Nickel Alloy Steel.

http://en.wikipedia.org/wiki/AISI_steel_grades

1997bird

iTrader: (2)

Like I said they are a two peice cam. S.A.D.I stands for Steel Alloy Ductile Iron. The rear dist. drive gear is Ductile Iron so that you may run a steel (mellonized) gear on your dist. without wearing the cam gear. The front part of the cam is a Steel Alloy billet and the rear section of the dist. drive is then pressed onto the front section. I am not sure if they are then welded together, when I check with my cam grinder in the morning I will find out for you.

Old SStroker

8650 has enough carbon (.50%) to allow direct hardening, much like 5150. The lobes are induction hardened and the balance not.

8620, with only .20% carbon content, needs to be carburized (case hardened) on the lobes in order to be hardened enough. The areas which don't require hardening require masking to prevent carburizing. This masking is often done by copper plating, and then grinding off the areas which need case hardening. This adds extra steps, and copper has become an expensive commodity, so induction hardening of "50 carbon" steels is now probably cost effective.

FWIW, stripping the copper after heat treating is also costly, so it is generally left on the cam. Doesn't hurt anything, identifies it as a case hardened cam and looks nice.