AMC/Jeep gear drive, that right there is rare as hen's teeth

[1992Rotbox]

This find deserves a new thread, there just isn't one on the AMC/Jeep dual idler gear drive.
I'm massing parts for a future stroker build. I run across an ebay item that says Pete Jackson gear drive 199, 232,258
I say HOLY SHISKABOB! MINE! Oh yeah! These gear teeth are as scarce as hen's teeth, I've NEVER seen one before, anywhere.

I did win the bid at $52 needless to say, Please help positively ID this artifact. Like finding a damn live dinosaur.
It's missing the cam bushings for indexing the cam timing, but its brand new and complete otherwise.
The crank gear is 24 tooth, it does mesh with the camshaft gear and idlers. Does anyone know the cam to crank distance for an jeep inline 6?

[SIXPAK]

I believe the distance is 5.045.

[1992Rotbox]

On a tape measure, I get 5 inches and somewhat less than 1/64. We have a winner.
Thanks Sixpack, that's the kind of engine block spec I could'nt seem to find even in an FSM.

[gradon]

Excellent score:

[racing89]

I was told that I had, one of about 6, of the pete jackson gear drives that hesco DIDNT get from direct connection. By the looks of your pics, thats the right stuff. Really good gear , Been racing mine for over 10 years!

[SIXPAK]

If you have one of 6 ever made then my buddy and I owned over half of the inventory! We had 4 between us, but I sold one to Plechtan so we are down to 3. Seriously though, I was told there were about 100 sets made.....who knows, that could be a tall tale too?

[4.whoa]

Has anyone tried to get them to start making them again?

[SilverXJ]

I saw one on Craigslist some time ago for $200. Maybe I should have purchased it.

I'd rather have someone come up with a belt drive than another gear drive.

[5-90]

Belt drive? Sacrilege! Belts are for accessories and holding pants up.

I'd love to have a gear drive on the shelf for when I finally get my stroker going (hint?) and I'd like to take measurements to see about designing a helical-cut set (runs quieter, less stress on the gear teeth, lasts longer.)

Sorry, but I honestly don't feel like changing the timing belt on my Jeep every 60K - the only reason we bought my wife's Suzuki Verona was because it had single roller chain timing (that was the big thing that sold it for me. No way I'd have signed off on it if it had a damned timing belt - if it had had a belt, I'd have had to change it twice in the last three years already...)

[SIXPAK]

I saw one on Craigslist some time ago for $200. Maybe I should have purchased it.

I'd rather have someone come up with a belt drive than another gear drive.

Jeep 4.0 Xceldyne Belt Drive...some assembly required!

[1992Rotbox]

Coolness, a belt drive. It needs a wider belt, and a much deeper timing cover to equal the strength of a chain.
But you can't beat the big plus on belt drive- it dampens crank harmonics. For a race motor, they are the best for the valvetrain stability.
and when they break, they are harmlessly chewed up on a non-interference engine.
Timing chains are by far the best of both worlds. Quiet, smooth, long-lived.

the rolling argument against gear drives is transmitting crankshaft harmonics into the cam. I intend to find that out sometime.
On the jeep's block the smaller drive gear will be on the uphill side, partly staying in place with gravity. The idler will be dangling on the downhill side. Those straight cut floating gears will deflect the cam towards the passenger side.
May need a custom timing cover to properly retain them. The soft aluminum timing cover will eventually wear, and the gears will walk. Will need a stout, wear resistant steel timing cover.

What could I do with this gear drive, that would be worth it? A destroked rev mule? A punched out, 12 counterweight axle snapper? Definately not a whiny stocker!
That's the other drawback, what do you do with the gear whine? Cover it up with a real supercharger?

[SIXPAK]

May need a custom timing cover to properly retain them. The soft aluminum timing cover will eventually wear, and the gears will walk. Will need a stout, wear resistant steel timing cover.
What could I do with this gear drive, that would be worth it? A destroked rev mule? A punched out, 12 counterweight axle snapper? Definately not a whiny stocker!
That's the other drawback, what do you do with the gear whine? Cover it up with a real supercharger?

I raced my gear drive for 18 yrs with a factory timing cover. The cam bolt was modified flat on the front face. It had a small recess in the face that accepted a 1/2-20 bolt that was turned down on the tip. On the tip of that bolt it had a small torington thrust bearing. There was a small housing welded to the cover with gussets and it was tapped for 1/2-20. Snub the bolt/thrust bearing to the cam after the cover was installed and back it off a touch. Sounds more complicated than it is though.
BTW, my gear drive never had a wine but with an agressive ramp roller cam and big springs it sounded like the motor was flying apart at idle! With the aggressive solid you never knew it was there.

[gradon]

When I looked at the 2.5" headers from 505 Performance that someone here was asking about I saw that they sell 4340 hardened gear drives, so new ones can be bought(for $420):
http://www.shop.505performance.com/cate ... egoryId=23

[Mr.Mopar]

Does Xceldyne actually make the Belt Drive? I can't find anything on their site.
What the part # and cost?

Thanks

[SilverXJ]

How would a belt drive work on a daily driver? I know that most of the aftermarket belt drives are pretty much a race only affair.