chevymans 77

I need to order a bronze gear for my HEI distributor so it doesn’t eat my Lunati billet roller cam. They offer a couple different sizes, .491” and .500” for the Chevy HEI. Does anyone here know the size of the shaft on the HEI distributor?

Thanks Neal

norvalwilhelm

I have run aftermarket distributors so long I forget but if in doubt I order the .491 because it is easy to ream it out to .500 if I make a mistake. All my aftermarket distributors have the .491. Be sure you need a bronze gear?? I ran them for years only to find my roller cam was ok with a normal steel gear.

Pete79L82

Stock Delco and most aftermarket HEI distributors with cast aluminum housings use .491 shaft. All MSD and most aftermarket HEI distributors with billet aluminum housings use .500 shafts.

If it is an aftermarket unit post what brand/model it is an I should be able to tell you what size gear you need.

Pete

gkull

I use the comp cams polymer dist. drive gear. It was still in perfect shape the last time I had my dist out. Bronze gears don't seem to last. They are a racing only item.

gkull

My lifters are Crane pro, The Gear is Comp Cams, and the billet roller is a custom grind extreem ramp profile with .620 lift on I&E

chevymans 77

Norval did not think about it that way, good idea.

Pete79 its an Accell replacement dist. I believe it is the same size as
the Delco.

gkull I will have to call Lunati and ask about the polymer gear, I want
the best I can get and would like it to last a little while to.

Thanks for the info guys I will give Lunati a call and see what they say.

ZD75blue

Whats the advantage of running a bronze gear anyway?

Isnt stock a steel gear?

Pete79L82

Chevymans77: All Accel distributors use .491 gear.

ZD75blue: The gear must match the type if cam core/gear that it is being used with. A cast core or gear can use a steel or bronze gear. A steel billet core must use a bronze gear (or melonized gear). A polymer gear can be used with either one. If you use the wrong gear you will get rapid gear wear. There is no performance difference from one to another, it is only for gear life.

Pete

ZD75blue

Is the polymer gear similar to the nylon timing chain? Eventually going to end up in pieces in the oil pan?



Does anyone polish the gears together, or is it standard operating procedure to just let them wear together on startup?

gkull

The Polymer is like brittle carbon fiber. They have made claims of testing out to 50K miles with minimal wear. I do know that bronze never did last that long in circle track cars and would not be a good idea for the street.

Like anything, proper assembly is what you have to have. I use a Morroso dist gear dept gauge and shim the dist. to it's correct height. On the other end you have to use quality timing parts to minimize cam walk. I have a cam roller button that keeps forward movement down to .003 - .004 Cam movement changes how the gears mesh.

dizzy070874@gmail.co

yes im building a 98 5.7 vortec my question is ive put a rv cam and im using hei distributor with the metal gear will it be ok thanks i seen your post and wonderd how you foundout the metal gear is fine