food nd cars

I know this has been discussed many times, but from my research I can't seem to find a solid answer on which gear is the best replacement. I have found that there are not many options other than stock or lunati and maybe one more that i cant name right now. From what I have seen the problem of the oil pump drive gears being worn down from Comp cams due to the billet gear that somehow chews up the drive gear.. I have seen a few of the stock and aftermarket gears getting messed up with both SV and HV oil pumps. What is the overall consensus about which oil pump drive gear to choose with (in my case an LE cam) any aftermarket cam?

I am using a melling stock replacement oil pump. Stock drive gear has some patterns but overall in decent shape for 100xxx mi. Like i said above a LE grind cam.

quik95lt1

iTrader: (7)

ive run both a stock gm and a lunati everwear with no issues on AI billet core everwear cam gear cams..........i ran a stock gm one for a long time and it looked brand new when it came out

93M6Formula

I don't mean to hijack but what exactly is killing these gears?

97LT1

iTrader: (3)

Some say it is from using a overdriven oil pump creating extra stress on the gears. Some say it is from the different metals used on different type cam gears I have reinforced my gear drive in the upper mounting portion, and reinforced it to hopefully extend the life. I am running a 10% overdriven melling select BTW.

Alex94TAGT

I haven't been attending the forums in recent years, but it was my understanding that this problem was ONLY an issue with the high-volume pumps (as they presumably produce greater drag on the drive mechanism, thus increasing forces exerted on the gears). Guess that's no longer true, eh?

To the OP, I've been running a Comp Cams solid-roller grind from LE/BB as well, for about 5 years now. I didn't swap either of the gears out. Stock-volume melling pump with high-pressure release spring in a canton pan. Never had any problems -- the stock oil pump drive gear looked okay the last time I had it out a couple years ago. I'm worried now that perhaps I should check it again.

Like 97LT1 above, I did make a metal retainer plate for the "dummy distributor shaft" / oil pump drive mechanism in the rear of the lifter valley, so perhaps that has helped. -Never liked the fact that a plastic tab is all that holds that thing in there, and I've heard of the plastic retainer cracking. I wonder if it's possible that those with "chewed up" oil pump drive gears were merely having the distributor shaft lift a little at high RPM, reducing contact between the gears' teeth, and thus chewing up the gears in the process. Pair that with excessive drag from a high-volume pump, and that sounds like a recipe for failure, regardless of bimetal contact.

Wicked94Z

iTrader: (26)

I've been running a HV oil pump for years with a stock gear and now an older Everwear with no abnormal wear issues.

Burning Rubber

iTrader: (1)

I have HV pump and a composite gear and have had no problems. However when I had the stock gear, I ran it with a SV and a HV both times the gear chewed up. This was two different stock gears.

"I wonder if it's possible that those with "chewed up" oil pump drive gears were merely having the distributor shaft lift a little at high RPM, reducing contact between the gears' teeth, and thus chewing up the gears in the process."

Both of my gears that chewed up were chewed up on the bottom of the gear. I also had a 1/4 aluminum plate on top of my oil pump drive.

joelster

There is a better option if you go with a single plane intake. You can run one of those "dummy distributors". They are designed for guys who run front mount distributors. Here's a picture:




I don't believe there is any way to machine a stock intake down to properly mount one of these though. The single plane intakes that guys use on LT1's are always for an sbc and have the hole back there along with the hold-down mount.

97Z28SS

iTrader: (5)

There is also another option, Shon Herron makes a billet aluminum housing and in conjunction with a composite drive gear you should be bulletproff. By the way it's for sale $250 shipped.

http://i1110.photobucket.com/albums/...T1parts014.jpg

http://i1110.photobucket.com/albums/...T1parts013.jpg

jasonisdn

iTrader: (1)

Hey 97Z28SS,
Did you have a decent amount of play with the drive gear on Shon's billet piece? I've been meaning to contact him in regards to it.

Alex94TAGT

Who manufactures that piece? Mallory?

Years ago, there used to be a company that would machine the stock LT1 intake for a rear-mount distributor, but I believe they went out of business. A good machine shop could probably do it, but you might need to use the single-plane intake as a template, which would arguably be self-defeating.

Depending on how it's made, I wonder if I could cut the top section off, TIG weld a tab to it and mount it like the stock piece. Wouldn't be bad for $70.

Shon Herron

iTrader: (25)

They are $130 shipped not $250.