I've broken a few 742 8 3/4's over the decades. It's always been the ring & pinion teeth. 1.47 best 60' in a 3,540+ lb 360 footbrake car. I've been using the aluminum cases, which may help overall. I believe that weight is a big factor. But it's difficult to pin down why other things, like an OEM cap, breaks before the teeth. Lots of variables. I put a Dana 60 in my 12 second 3,930 lb Aspen and haven't changed the rear in the Dart yet. Peace of mind.

This year I could have run a 8.75 as my car has been on jack stands 99% of the time. When I get back to the track, I prefer my S60.

I have done this, as my Dart got quicker the parts attrition got worse. 60' 1.39/1.40 normally now, 3375lbs Nod 489 case, 35 spline, magic pink goo shock proof oil, back braced. I run a 4.30 gear which is probably the worst but it is what the car wants.

I race often it got down to 2 ring and pinions a year, Richmond, Motive, Yukon had them all. I did a 9" and am very happy with it. You will be money ahead in the long run to just upgrade to a tow truck rear or a 9"

I had to type this out 3 times to remove the cutting sarcasm, cuss words, and bad attitude I have on this subject

Thanks. That settles it

"You can brace it like a tank and it will NOT fix the inherent weakness of the 8.75. Torque pushes the ring gear away from the pinion when the case flexes. You CAN'T fix that. They break caps because all the debris from the shelled teeth gets in there and it pushes the cap off. So you will spend a lot of time and money trying to fix a problem you can't fix and it will eventually break anyway." Monte Smith

. I'm going to have to say it was being built wrong for you to have broken that much stuff in a 10 second car.. guys like Thumper have been using the same one for 17 years.. that being said there is no substitute for 9inchs

[/quote]. I'm going to have to say it was being built wrong for you to have broken that much stuff in a 10 second car.. guys like Thumper have been using the same one for 17 years.. that being said there is no substitute for 9inchs [/quote

Ha ha You sir are still a A..hole (and a friend)

The cut off point in mine was reached last weekend. Shelled teeth off the ring gear even with all the band-aids, but that's with a car that weighs 3800+
I'll be purchasing a Dana 60 next month.

I’ve had no issues with either the stock or Nodular 489 case launching at 4500 dead hooking on Drag Radials off the brake at varying weights between 3300 and 3150. 250+ launches off the stock case, while I worked through traction issues to boot. Last weekend it went 6.30 in the 1/8mi with a 1.36 60’. No doubt a Dana or Ferd 9” are tougher, but needed? The data in my book suggests otherwise for a 3300 lb car running 10’s.

I’m sure if we search enough we can find somebody who’s had no prob with HP and his 8 1/4 too.

& when that 8 3/4 lets go & takes out that expensive 727,a518 mopar auto trans, THEN the 8 3/4 size tears will flow

Come on Dom, we all know you go to the track for a couple passes like once every 2 years.
Beating on it on the street will never duplicate the traction/stress it will see at the track. Lots of weak parts can live a long life w/ no traction.

Thank you!

Why did the factory put the dump truck rear in stick cars? I mean come on! They already had 8.75s that would fit.... and these were street cars... with tiny skinny tires!! What were they thinking!!

I ran a 8 3/4 and still do in the race car.. the
car is light but it blew the ring and I changed
to the alum center.. its had a back brace all
along.. when I built the hot rod I put a 9" in
it with a back brace and DRs.. had slicks in
the race car and a brake with 1.19 60'.. both
are still running strong

Your welcome and I will post a pic of my fat ass time slip book then you can tell me how I've only raced a couple times a year..........Don't be hatin on my quick ass n/a street car.........

I still run the 742 8-3/4” that came with my car from the factory. After breaking a couple of sure-grip differentials, I now run a spool, along with a steel cap on the driver side, 35-spline axles, and my housing has a brace stitched onto it. My car doesn’t make power like most on this board, but I do throw more weight at mine than most, as my car crosses the scales at a solid 3870 these days. It 60’s in 1.53,the footbraking.

I know a guy here locally that runs a low10-second 67 GTX on a trans brake. He still runs an 8-3/4”. My belief is that 8-3/4’s have their place. A 9-second B-body may not be that place.

For all those that call the modifications “band-aids”; the 9” units that most run are not stock Ford units, they’re full of aftermarket stuff also. For that matter, most Dana’s in this conversations are likely S60’s outfitted with Spools, aluminum covers, and aftermarket axles.

Don did not mention his car is a ladder bar car that will be another add expensive of switching over to the dana the hp your going to make will be fine with a new housing and axels

I agree: No stock Ford parts at all I was told by Joe Reath back in the early 1970 that their funny car, Dunn and Reath, where the test mule for the Chrisman family helping develop the Ford nine inch for drag racing. He said they where into it back then for around $2300.00 and still would put the Dana 60 back in the car to go to certain high altitude low traction tracks like in Salt Lake so they didn't have to change third members at the races due to carnage at those tracks
As far as Dana 60 used for drag racing in some cars I normally will use a junk yard damaged Dana 60 core due to the lower price and I'm going to have them cut down and narrowed to fit and use after market spools and axles
The truck rear ends set up properly will push by hand in the car so much easier than any 9 inch Ford equip car I have help push at the races or any where else, same thing on drag cars with 8 3/4 rear ends in them when it comes to pushing them by hand