Okay all, I dyno'd my Barracuda,
1968 coupe, 543 stroker, pump gas- 531- HP and 597 TQ at the wheels

Fun spirted drive.

1st gear spins the tires, 2nd gear spins the tires 3rd gears makes horrible sounds, grinding, clunking, banging and then the engine just revs.... 4th goes just fine.

I think its broke. Ill pull it apart in a few days for carnage pics.

You killed 3rd gear. Either the speed gear or cluster. Libery makes a 9310 gear set that might live longer if you refrain from operatibg the car in the manner stated above.

Spinning hard and dead hooking it on the upshift will do that. Much like rolling a mechanical diode in a 727.

What clutch is in the car and how much does it weigh? You need something that slips a bit on WOT engagement.

What about cryo treating the gear set?

The clutch is a twin disc setup. No slip. I was thinking about adding a clutch tamer to it.
Or do I stop with this 4 speed and go to something a bit stronger?

I broke some 833 18 spline stuff with a Mcleod Street Twin but my Richmond 5-speed held up OK but it has cryo treated gears when I had them face-plated at Liberty's.

I'm running a street HEMI box now with dual friction clutch now with good results.

Gus

Time for T-56 magnum... I beat the living crap out of mine as far as spinning/hooking and no problems

what is your power level?

As long as you don't make more than 600 HP or close to that,HUH

i dont make that to the wheels... what about a slipper valve? This would alleivate the harshness of dumping the clutch. Ive looking into clutch tamer before but didnt see the benefit at the time. LOL, Now Im thinking if I went with something like the mechanical clutch master slipper it would be in ever gear and would STOP me from shocking the gears the way I did.

The clutch Tamers are adjustable
Jeremia uses and loves them

here is the damage....

If you shift using the clutch pedal, installing a ClutchTamer will definitely help keep your transmission alive.

The most important thing a stick shift drag racer can do is to soften the clutch's engagement rate to compliment the engine's power. Not only does that keep the engine operating up where it can make the most of its power potential, doing so also softens the impact on the rest of the drivetrain. It's your basic win/win.

The first unit I made 12+ years ago I called the "Hillbilly Clutch Slipper", basically a $12 hydraulic screen door closer I bought at the local hardware store. It worked pretty much the same as the units I currently make, but as you can imagine many originally thought the hillbilly slipper was a joke. Here's a link to info showing that original install- Hillbilly Clutch Slipper

Fast forward to today, there are now winning NHRA racers using basically the same setup to further soften launch engagement of top shelf adjustable clutches. Much shorter cylinders now, but they effectively do the same thing that the original hillbilly slipper did. It's become one of the most cost-effective things a stick shift drag racer can do. Here's a link to a page of mine about applying nitrous in a clutch car, but the top part of the page has a couple graphs that show how slowing clutch engagement rate can affect the peak impact seen by the transmission's input and driveshaft. Note that 3rd gear gets hit the hardest in this G101a example... https://grannys.tripod.com/clutchtuningnitrous.html

Grant

It's important to note that the 'tamer isn't just for street/strip cars, it also helps dedicated race cars. The same 'tamer you would use to soften the hit of a street/strip clutch is the same 'tamer you would use to further soften/improve the hit of a $$ adjustable clutch.

Here's a quote from earlier today about a NHRA class car after installing a 'tamer-

"Last weekend we ran one in a record holding 67 Camaro with a soft lok and no CW and first weekend out it picked up, just like the other car we run with the exact same set up… and most importantly they ain’t burning [censored] up or calling a clutch expert weekly to tune their clutch."

Grant

Should make around 600 wheel... that's nothing for a magnum... guys running 8s with that trans with 1k HP

Looks like a stock 18 spline tranny with a wiped out cluster gear. Okay, I've been street racing and drag strip racing for many years. I've learned the hard way that 2 things have to slip. Either the clutch or the tires with a stick car. Your choice. Over the past 40 years, I have never broke a tranny or rear gear. My car is a street strip car that has dipped into the high tens. Most of the time it is in the very low 11's. This with close to a 2 ton car!!! My combo is very conservative.. 11' Dual friction, 18 spline slick shifted tranny, 4:56 gears with a 29" tall tire. My engine make over 580HP at the wheels. I don't know how you shift. I've never seen you or know you, with that, Granny shifting is very hard on the drive train. Power shifting will lengthen the life of drive line parts. It's pretty hard to power shift a stock tranny above 5000 rpm. Also, what type of gear oil are you using? All of this is my experience and opinion. Take it as you like. I'm just trying to help.

well thanks for the input. I wouldn't say I was granny shifting when it broke. I just tapped the clutch to help it release and banged it into gear. well... where 3rd gear used to be. It shifted like butter even at 7k. after i replaced all the synchros and had the gears deburred and the cleaned up

I'm wondering..... if i rebuild this 4 speed do i replace all the gears in the trans and all the bearings? I just rebuilt it a few months ago, maybe 1000 miles on it since then.

I was using sta-lube gear oil for this type of trans.

My other option would be to sell all my stuff off- my 540, the headers, holley MPFI, whats left of the 4 speed, the shortened d60 and go in a totally different direction with the car. But i dont think anyone here likes the ideas of battery powered cars so I wont go into that.

68lar and weedburner have the info you need to male this work. The a833 will be just fine if you can drive it like lar said. Unloading and loading the transmission/drivetrain during a WOT upshift will break any of them. T5, gf5r, g101a, jerico w/ever

I have been having awesome luck running Redline heavy shock proof in my a833. Much less metal at service intervals and the trans is much quieter than with MTL. I am going to experiment with medium weight shock proof this round.

Replace the cluster and have it face plated if you plan on WOT shifts. I started with new 9310 speed gears and a 8620 cluster and have yet to break any hard parts. I did break the inner race of the rear mainshaft bearing however I think that was due to an oversize journal on the aftermarket mainshaft.

I would never go back to synchros in a hotrod after have a face plated box in a few cars.