4 speed strength

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75greenduster

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How much horsepower will a stock A833 handle without worries? My 360 will probably put out around 400hp and I am wondering what my best bet for a transmission would be. I would rather not have an auto.
 
The A-833 4spd trany will hold 400 HP, all day, every day, for the rest of your life unless you start doing stuid things akin to auto tarnny neutral drops, allowing the pedal to come upby sliding the foot off to the left and letting it slam up while at W.O.T. & high RPM's, Poor clutchless shifting. (AKA, beating the snot out of it.)

HP wise, these trannys give up or live a short life after a 550 HP mark and track use as a combo. The shock they recieve between the hi hp level and super grip of the track cause a big shock at launch and shorten the trannys life preety much down to months (If it's mint to begin with.)

(From the been there done that crew of the school of hard knocks & stupid manuvers)
 
mopar installed them behind max wedge engines in 1964. the max wedge puts out a lot more power than a 360. they seemed to live behind those motors. i have one in my 340 duster, have been racing it since 1978.
i have found, that mobil 1 synthetic gear oil does improve gear life and shifting.
 
They are pretty much bullet proof behind a small block . I am using the same 4 speed I used behind my built hemi car in my small block cuda. I just took it apart to check it after 4 years of hard driving and it looked like new inside, so I dropped a pair of bearings in it just because I was in there and it works flawlessly again. I use ATF in mine without a problem
 
rumblefish360 said:
HP wise, these trannys give up or live a short life after a 550 HP mark and track use as a combo. The shock they recieve between the hi hp level and super grip of the track cause a big shock at launch and shorten the trannys life preety much down to months (If it's mint to begin with.)
Click to expand...

What all can you do to them to beef them up to handle the extra horsepower? I'm looking at dropping a 6.1 hemi in a 67 Dart that's got a 318 and 4 speed in it now. I expect a cam swap to start with and probably some boost down the road, but I'll deal with that when I get the money. I figure with the cam I'm looking at around 450 hp, and I do intend to weekend race the car, though I will be driving it on the street primarily. I probably won't be racing too terribly often, but I figure maybe a few times a month. I probably won't completely murder the car on launches, but I certainly won't be just rolling off the line (where's the fun in that =P). I'll probably drop some street slicks on it, maybe a backup pair of full race ones at some point, so I expect some fairly decent abuse.
 
Map63Vette said:
What all can you do to them to beef them up to handle the extra horsepower? I'm looking at dropping a 6.1 hemi in a 67 Dart that's got a 318 and 4 speed in it now. I expect a cam swap to start with and probably some boost down the road, but I'll deal with that when I get the money. I figure with the cam I'm looking at around 450 hp, and I do intend to weekend race the car, though I will be driving it on the street primarily. I probably won't be racing too terribly often, but I figure maybe a few times a month. I probably won't completely murder the car on launches, but I certainly won't be just rolling off the line (where's the fun in that =P). I'll probably drop some street slicks on it, maybe a backup pair of full race ones at some point, so I expect some fairly decent abuse.
Click to expand...

I wouldn't wory about it at that power level or intended use.
 
75greenduster said:
How much horsepower will a stock A833 handle without worries? My 360 will probably put out around 400hp and I am wondering what my best bet for a transmission would be. I would rather not have an auto.
Click to expand...
An A833 23 spline 4-speed will be fine behind 400 hp.
 
Map63Vette said:
What all can you do to them to beef them up to handle the extra horsepower? I'm looking at dropping a 6.1 hemi in a 67 Dart that's got a 318 and 4 speed in it now. I expect a cam swap to start with and probably some boost down the road, but I'll deal with that when I get the money. I figure with the cam I'm looking at around 450 hp, and I do intend to weekend race the car, though I will be driving it on the street primarily. I probably won't be racing too terribly often, but I figure maybe a few times a month. I'll probably drop some street slicks on it, maybe a backup pair of full race ones at some point, so I expect some fairly decent abuse.
Click to expand...

"I probably won't completely murder the car on launches, but I certainly won't be just rolling off the line (where's the fun in that =P)."

When you race a 4-speed, you do whatever the car likes, and if that is rolling off the line... then you roll off the line. Behind slicks and boost, a 23-spline isn't going to last long. An 18-spline would be an upgrade, but you will need to stay on top of wear and tear. That means extra gearsets, clutch components, ect. That is going to cost $$$.
I have a good friend who has a 6.1 with boost and slicks in his street/race car and he has extra transmissions.
A better bet would be an aftermarket trans meant to take hard use.
 
I ran 18 spline units behind some serious horse (5-600) B Body BB's for years and abused the hell out them, didn't break even one. Clutches well that's a different story.:angry7:
 
A-833's can handle pretty much everything you can dish out but you have to be careful as mentioned above.
You can do a "slick shift" modification for drag racing, or use the nash-5 speed which is suggested as a beefier unit but needs mods to work in the A body with the trans tunnel and trans mount via Mopar chassis manual vol-9.

I highly suggest getting the Mopar performance Chassis volume-9, Speed secrets and performance modifications- to answer many of these types of questions for hot rodding mopars.
Part# P5007160 $30.00
 
if you do go with the A-833, make sure you have it gone through before install, as well as make sure your rear main seal is bone dry.

Any fluid contamination of the clutch with defeat your chances of hard launch and breaking the tires loose i/e slipping clutch.
Ask me how I know.....better yet, don't ...LOL.
 
Map63Vette said:
What all can you do to them to beef them up to handle the extra horsepower? I'm looking at dropping a 6.1 hemi in a 67 Dart that's got a 318 and 4 speed in it now. I expect a cam swap to start with and probably some boost down the road, but I'll deal with that when I get the money. I figure with the cam I'm looking at around 450 hp, and I do intend to weekend race the car, though I will be driving it on the street primarily. I probably won't be racing too terribly often, but I figure maybe a few times a month. I probably won't completely murder the car on launches, but I certainly won't be just rolling off the line (where's the fun in that =P). I'll probably drop some street slicks on it, maybe a backup pair of full race ones at some point, so I expect some fairly decent abuse.
Click to expand...

You won't hurt the trans it will take out the ring & pinion or U joints first, it you go to a Dana60, 1350 joints and slicks it will tear up the clutch. I knew someone putting 700+hp thru a 23 spline and eventually hurt 3rd gear but it was a 470" motor with 440-1 indys and spray.
 
Brewer's swears it will take whatever you throw at it until 3rd gear has had enough of bank shifting..............that is the weak link! But hey you drive them hard something is going to break eventually.............no doubt!
 
My last foray before I sold my motor to a restoration guy. This is a pro-stock cluster gear I smoked a couple years ago, from an 18-spline full race 4-speed that was LIGHTYEARS stronger than a 23-spline. This was done with a T/A 340. 12.1 comp. 4.56 gears and slicks. This wasn't even a violent launch, and yes, 3rd is the weakest link. As you can see I got off the gas quick, but the damamge was done.
Stories of 23-splines living up to 700 hp ect always mystify me...I've blown 18-spline race transmissions up with much less. Of course I am only interested in nostalgia so I use Chrysler or Liberty products, otherwise I would have saved a ton of cash and gone with an aftermarket solution.

cluster.jpg
 
i think there are so many factors its hard to say. A lighter car with more rearend gear and a good clutch even with 500hp will last longer than one with the same or less hp but heavier and with not so good clutch or steep rearend gear.

I think a 23 spline would be fine behind a 400hp smallblock no problems...but with the setup you have in mind for the future, id atleast step up to an 18 spline with a good clutch..Mind you though, theres no fun in driving a stickshift if you arent dumping the clutch and powershifting...mine as well just buy an auto imo

the interesting thing to consider though is that before the nash boxes came out, the mopar 833 18 splines and ford toploaders were the standard in 10/9 sec cars...keep in mind though like outsider mentioned that you will need to regularly maintain them to keep them running at those levels, and you will eventually break stuff too...its all in the clutch!

good luck!
 
Yeah, the more I think about it the less I inted to race the car regularly. I think I'm more interested in a really fun driver car that I can take to the track and have a lot of fun with as well. I figure I'll probably take it a few times a month, but not necessarily every weekend. I will probably be hard on it when I take it though =P. I was pretty insistent on the 4 speed, you just gotta love banging the gears yourself. I don't know why everyone goes auto, though I understand some since I've done some parades before and a stick will KILL your leg. Not to mention if you hardcore race you can't beat consistency. I like the idea of training myself to be consistent though instead of just mashing the gas at the green, more fun that way =P.
 
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