455 won....

455 won....

#2

#3
10 bolt was factory 3.42 ratio $$ miles as it came from the J-yard but had new arrier bearing and a Cast Aluminum rear cover with supports .

60 its last 60 foot was a 1.60 but car could run in the lower 1.5 if I wanted to launch that hard. Its best was 1.57.

So should I re-gear it and try it again ??? maybe new gears would last ????
IF so what gear...3.73 was my first thought. The car ran 7.28@97 in the 1/8 at about 3900 lbs with 5 speed man trans (TKO)
28x10.5 MT et drags or 275/60/15 et drag radials... I think its safe on the radials because they spin if you launch it hard at all.

Mass destruction!! http://forums.performanceyears.com/g...s/icon_eek.gif

That is typical damage. The gear came out of mesh, probably from deflection.

The 10 bolt is a strong diff. I have seen them take much abuse. You could beef it up slightly with a TA type rear cover with the preload bolts that go against the caps. Set the backlash at the minimum tolerance as well. The factory posi unit might be the culprit. It is possible that it is flexing.

It had the TA type rear cover with preload bolts FWIW. Back lash was a measured .010 when it was put back togeather and ran very quite until the end ..RIP.. It had probably about 40 slick launches maybe 20-25 in the 1.6 range 2-3 in the upper 1.5's.

My greatest fear. Well second greatest. Better an old set of rear gears than a new set of tranny gears. I've always thought my ST-10 would go before the 10 bolt rear when I can 60 ft. well enough to hurt something. I guess the TKO is working well for you?

My ST-10 went before my 10 bolt 8.5 rear with 3.42. I installed a Tremec TKO. I hope my rear doesn't end up looking like this one! RIP

I got REALLY GOOD at swapping out 10 bolt A-Body rear ends in my GTO (many years ago)
until I finally got smart and put a 9" Ford Moser rear housing under the car.

I broke 12 bolt rears too.

Tom V.

was that a factory gear set? hp aftermarket ring and pinion set are better im sure..

Probably would have helped if you had the after market cap installed. That will reduce deflection.

I got the rear from the J-yard, I believe it's a factory original gear set. Is it worth rebuilding it and trying again with a aftermarket cap ? ???

I'd stick another gear in it. Not sure the aftermarket caps would help much in this situation. Try to set the new gear up so that the pinion meshes more towards the inside of the gear, that way under load it will mesh towards the center of the tooth, rather than the outside of the tooth (which is what ripped the teeth off of this one). If it does it again, you only blew $175 on new gears. Those gears were likely factory gears, which are probably more brittle than what the aftermarket "street" gears are today. If the posi needs work now, no sense in spending more money in this rear, get a 9"...but if it's still ok, just stick another gear in it.

My car has alot of low 1.50 60 fts on its 10 bolt with no cover.Precision Gears and an Eaton carrier. Switched carriers mainly for the easier rebuidability of the Eaton 4 spring in place of the S spring. Stock carrier was in need of new clutches.

A steel cap won't really help much if you have the TA cover. The .010 backlash should be tightened up a bit and put the pattern on the "toe" as Brian said. Precision gears are good, but hard to find. Try and spend some extra time to see if you can find them.

I've been running their "street" gears in a 12 bolt for years and 1.42 60/ft times and a 4 speed. I launch at 6000rpms and have never broken the gear set (knock on wood).

Looks like you may have got lucky man!!! I bet you will be fine with a new gear set.

3.42 - definitely lower it to 3.73 or even lower. You have an overdrive!

ok, So where to find these precision gears ? The posi was working fine but what about the metal from the broken gears... wash it out and blow it out with air and run it ????? what about the carrier bearings.... do I need to replace all this ??? it did this on the track and a limped it back in to the pits and back on the trailer that's all.
I'm gonna have to study up on the gear mesh topics I guess it will be my first rear rebuild..

3.73 would get me to about 5500 RPM in the traps at the 119 to 120 mph traps the car indicated it was wanting to run last week I don't want to use OD in a race and the cam is only a 236 hyd so its peak hp power is about 5400 rpm...so spinning to 6k is probably a waste of time.

OK- so 3.73!

For the cost of bearings and such, replace it all. Wash the tubes out completely with some carb cleaner or I use brake clean. There are pockets in between where the axle tubes press into the housing and the cast part. You get to them right next to the side bearings in the housing. Those places hide metal......very important to clean the housing thoroughly. Remove the axle bearings if possible.

Do a search online for the gears. I'm sure you can find something.

See if Tom's Differentials has them. I think that's where I got mine.

You can't get a "pro" gear for the 8.5" 10-bolt...they don't make them, so you have to go with a "street" gear. Any of them will work, even Richmonds. Some have complained about Richmonds being noisy, but I've never experienced it myself (maybe because the exhaust was always too loud to noitce?).

Always use brake cleaner, carb cleaner doesn't do a damn thing, and leaves a gummy residue.

Richmonds have always set up well for me as also.

I have never tried carb cleaner Brian.....thanks for the heads up.

Dewayne,

My rear end man states that new oem gears are better than the current Richmond gears, which are no longer "run in" as they were before, causing gear whine http://forums.performanceyears.com/g...icon_frown.gif .

He was able to obtain new 3:08s for my Eaton posi-equipped Chebby 12 bolt rear. My 66 has more than 300 passes with 28 X 11.50 Hoosier QT Pros in the mid 1.7 range.

Les

Here's a link to precision gear's website.

Weld the tubes and the perches.Take the bearing caps and grind to adjust 'rock' on bearing for .000/001.Deburr the carrier.Tom's Differentials HELPED me as Skip said.I had 60 + runs on 9"x30's 1.50/1.54 60's before I broke either the crossshaft or the spiders.I do confess I didn't do any maintenance as I probably should have.If you plan on drag racing more this is the way to go.Tom will give you the correct parts.

Call Zeuss at Tom's differentials in Paramount, CA. good people to deal with, and they know 10 bolts well, they sell an aftermarket steel cap for the driver side that also uses a larger bolt diameter also they sell c-clip style axles that are STRONG and if you are running those toothpick stock axles with c-clips, these are nice replacements (of course they are no replacement for clip eliminaters) Precision gear sets can be purchesed thru a company in Bohemia New York they are called Powertrain Truck and auto parts inc. Talk to Ronnie they have exellent prices and service.

Bad news about Zeus 72firechicken,Big Injun posted in this thread HERE that Zues had been killed in a motorcycle wreck. http://forums.performanceyears.com/g...icon_frown.gif

He did say Tom was still running the place though.

Here is their website.Tom's differentials

At the end of the year they have some smoking deals om stuff in inventory! They are the one that al the big magazines use for reference on 10 bolt and often 12 bolt stuff.

Tom had told me years ago the stock posi is the wek spot even over the axles I guess SDBob found that out.

For a killer "stealth 10 bolt ("gosh a real race car has to have a 12 bolt, that car must not be too fast")get a 30 spline Eaton posi and some aftermarket axles, I think even 12 bolt axles can be used but the ends may need grinding to fit the cross shaft.

Tom is running the place but they have shut down the office/warehouse in Southern California. Tom's, formerly known as Peppe's has been in Southern California for as long as anyone can remember, at least from the 1950's.

Tom's has a warehouse/office in Utah. Tom a few years ago decided to retire but stay active in the industry and built a warehouse/office in Utah. That location is now the headquarters.

Just talked to gary at Tom's. Very helpful,Tom is active from waht Gary told me f rom his office in Utah.