cloyes cam sprocket doesn't fit sbc block!

rustang · Post by **rustang** » Sun Aug 17, 2008 6:06 pm

This is a cloyes set for the factory style chevy hydro roller cam. Part number is 9-3145. The problem is it collides big-time with the top oil passage that runs between the lifter gallery (this is a ZZ4 block). It definitely is designed for the retainer plate but compared to the factory gear it's a lot smaller dia.

What gives?

Keith Morganstein · Post by **Keith Morganstein** » Sun Aug 17, 2008 6:46 pm

Can you grind the area of block? I do this on many SBC's with double roller, not just the factory roller cams.

The EPG factory roller sprockets usually require some clearancing too.

af2 · Post by **af2** » Sun Aug 17, 2008 7:50 pm

The GM single roller is pretty darn beefy and clears. More$ than the Cloyes but no headache.

1989TransAm · Post by **1989TransAm** » Sun Aug 17, 2008 8:23 pm

Yep, a common problem with the later GM blocks. Like was said above you have to grind off part of the boss for clearance. We do it all the time. At least you noticed as a lot of people do not.

rustang · Post by **rustang** » Sun Aug 17, 2008 8:30 pm

Keith Morganstein wrote:Can you grind the area of block? I do this on many SBC's with double roller, not just the factory roller cams.

The EPG factory roller sprockets usually require some clearancing too.

It looks like it could be ground for clearance. It looks like it might have to get pretty close to the end of the oil gallery bore. (it has press in plugs)

Kinda sucks since the block's all cleaned up, crank's in, etc. but that's not the first time I've been down that road

I'm kinda surprise because when it was ordered there was a note about the timing chain not clearing the stock timing cover, but no caution to "remove half the cylinder block"

What is "EPG"?

CNC BLOCKS · Post by **CNC BLOCKS** » Mon Aug 18, 2008 8:18 am

Those blocks do require a lot of grinding above the oil galley hole.

Racerrick · Post by **Racerrick** » Mon Aug 18, 2008 10:56 am

Get the single roller it should clear without grinding.

rustang · Post by **rustang** » Mon Aug 18, 2008 12:58 pm

Racerrick wrote:Get the single roller it should clear without grinding.

How do they stack up reliability-wise?

af2 · Post by **af2** » Mon Aug 18, 2008 1:03 pm

If you ever see one you will be surprised at the size of the rollers. About twice the size of the double roller chain.

ProPower engines · Post by **ProPower engines** » Mon Aug 18, 2008 1:03 pm

Cloyes lists a a timing set Part#s as follows
Hex-a-Just 9-3145A
***************Premium billet true roller 9-3645X9******
*** Original true roller 9-3145** the one you tried
Billet true roller 9-3545X9
Street true roller 9-1145
These are all listed for a 1985 and up with factory roller cam.
I think the 1 you choose is the same top gear as the older block
I use the billet set as I have seen the cast top gear loose teeth.

rustang · Post by **rustang** » Mon Aug 18, 2008 4:43 pm

ProPower engines wrote:Cloyes lists a a timing set Part#s as follows
Hex-a-Just 9-3145A
***************Premium billet true roller 9-3645X9******
*** Original true roller 9-3145** the one you tried
Billet true roller 9-3545X9
Street true roller 9-1145
These are all listed for a 1985 and up with factory roller cam.
I think the 1 you choose is the same top gear as the older block
I use the billet set as I have seen the cast top gear loose teeth.

Do any of these clear the casting?

ProPower engines · Post by **ProPower engines** » Mon Aug 18, 2008 5:52 pm

The last 4 premium billet sets I used did. Unless you have a really bad core shift it should fit fine.

Eric68 · Post by **Eric68** » Mon Aug 18, 2008 7:21 pm

The last two new GM blocks I've done had the same issue with the Cloyes double roller. I just taped off the block real good, ground away, and sprayed the front of the block down real good when done.

af2 · Post by **af2** » Mon Aug 18, 2008 8:38 pm

Eric68 wrote:The last two new GM blocks I've done had the same issue with the Cloyes double roller. I just taped off the block real good, ground away, and sprayed the front of the block down real good when done.

Geese! The single works on all engines going more than 100,000 miles!
Why make extra work when you don't have to?

Racerrick · Post by **Racerrick** » Mon Aug 18, 2008 11:42 pm

rustang wrote:
Racerrick wrote:Get the single roller it should clear without grinding.
How do they stack up reliability-wise?

Never failed one yet.
An old oval track engine I built many moons ago broke a piston at 7500rpm. Everything was destroyed as it blew to pieces and ventilated the block. The cam came out in 4 pieces! The single roller chain was still intact.
I'd say thats tough enough.
A double roller would have broken in half for sure.