quote:

---

Originally posted by Daniel Jones:
Steve Grossen had a lot of trouble with Comp. He kept eating distributor and cam gears on his 351W with a Comp 280H. Comp replaced the cam several times before bothering to check the cam gears. Seems they had a batch of cores with improperly machined gears. I had a similar problem with a Lunati, another friend had some problems with Crower etc. It probably gets back to the fact that there are only a handful of people that make the cam cores and the fact that the cam companies only do statistical sampling. The worst part of dealing with cam companies are the tech lines. Call them three different times and get three completely different answers.

Dan Jones

---

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

I know steel gears have been used with hydraulic rollers, but am not all that certain if they are compatible with steel solid roller cams.

Maybe someone has more information.

Good Luck!

I only know the 351w because the Comp bronze gear came with a warning to check it. Maybe it's the same.

Possibly but it can also be due to inadequate lubrication, improper
end play and/or gear palcement, and incompatible materials. Comp
lists their hydraulic roller cams and certain street solid roller
profiles as being compatible with OEM cast iron cam gears. I called
Comp several time to discuss this. A couple of their techs obviously
had no clue but on the third try the tech I spoke with (Dennis) had
a consistent story. He said their -8 part number hydraulic and street
roller cam cores are austempered ductile iron. A surface treatment
hardens the cam lobes so they can run a roller lifter. He also said
either a cast iron or cast steel distributor gear is compatible with
the -8 cores to run with the cam. Not compatible are machined steel
gears like the Crane 351C part which is made of 8620 steel, the same
as a solid roller gear. He said the OEM and Ford Motorsport steel
gears are a cast steel and would work fine with their street rollers
but not their race rollers. Unfortunaely, Ford doesn't make one for
a 351C. Solid roller cams are usually ground on 8620 billet cores
and require bronze distributor gears. It may be possible to use a
machined steel gear like the one Crane makes (though Mike Trusty had
trouble with his) but not an OEM cast steel gear.

Jim Sams was telling me about a guy on the 351C forum that was also
eating gears and finally solved it with a special Mallory gear.
Mallory lists two replacement gears. The more expensive gear is
aluminum/bronze for use with steel roller cams. The cheaper one is
is listed as machined from "alloy steel", heat treated to give the
proper hardness when used with "proferal billet camshafts". The
phone tech claims the "alloy steel" is the one to use with cast iron
flat tappet cams but I forgot to ask about street rollers.

I have about 4000 miles on my XR274R-10 roller so far and haven't seen any changes in the timing or anthing else unusual. This is a 351W cam in a 302 block. I run an old stock distributor and also a stock type blueprinted oil pump. I have turned it over 7000 just a few times but it sees 6000 rpms on a regular basis. Maybe there's something your overlooking that is causing it. How often is it eating the gear??

quote:

---

Originally posted by Daniel Jones:
>

Jim Sams was telling me about a guy on the 351C forum that was also
eating gears and finally solved it with a special Mallory gear.
Mallory lists two replacement gears. The more expensive gear is
aluminum/bronze for use with steel roller cams. The cheaper one is
is listed as machined from "alloy steel", heat treated to give the
proper hardness when used with "proferal billet camshafts". The
phone tech claims the "alloy steel" is the one to use with cast iron
flat tappet cams but I forgot to ask about street rollers.

Jim, do you remember any more details?
Dan Jones

---

Mallory makes a special geat for their distributors that is specially made for "austempered ductile iron billets" and "Proferal billet" cams.
Now I do not know if this is the standard off the shelf gear or not. I will have to find this out soon however as I am swapping to a (nearly free) Hyd roller setup.
Also be aware that Steve Grossen found out that "Pep Boys" distributor gears are not the same hardness as OEM Ford gears.
A guy on the Cleveland forum had trouble with OEM iron gears and went to the Mallory "Austempered" gear and problems went away.
As far as HV pumps go, I have one also but my gear wear on teh faild Isky cam looked fine.
I may go to the std pump with the moroso spring now though.