Dana 60/8-3/4 question

[G-man]

Hi

A Dana 60 will handle whatever power you throw at it but it is also SIGNIFICANTLY heavier than a 8-3/4 with an alluminium casing.

Is there any way to make a Dana 60 lighter?

Is there a way to beef up the 8-3/4 to handle what the Dana would? (i heard you can if built propperly and much lighter to)

Curious about it.

G-

[69charger440]

Well if you have enough money anything is possible! How much power are you putting out?

[motorcitydak]

For the dana 60, you can toss one of these covers on it. The studs preload the caps on it so they cannot deflect. You can also have all the internals sent to be cryo treated (cryogenically frozen which realigns the molecules).
http://www.justdifferentials.com/index.php?main_page=product_info&products_id=211&zenid=17211501ca23a475463f0afaee41be2c

8 3/4, you can cryo all the parts, thats about it.

Most of you guys know my other response to this problem, but the purists will not like it

edit-sorry, I forgot to put the link to the cover I was talking about

[Blown70]

Most of you guys know my other response to this problem, but the purists will not like it

[motorcitydak]

Most of you guys know my other response to this problem, but the purists will not like it

*cough*9 inch*cough*

[Blown70]

G-man sorry to respond to your question, there is really not a way to make a Dana Lighter, with the 8  3/4 can be made to handle good HP, but not outragious HP, and can depend on the amount of wheel slip, if you have Sticky tires and high HP is a matter of time...  I guess, all being equal I would go with a dana and beef that up.

9 inch.... hahahha

[Blown70]

Whilest I was busy hacking on Motorcity,,,,, I thought, what is the application your using the rear for?  Street, racing, etc?

[G-man]

I was thinking behind a 528 all alloy hemi. Around 580 hp and the max torque u can get out of it (620+)

15" wide radials on the back... if I ever stuck a 15" wide slick... and hooked hard...

Its a cruising car with occassional drag so im kinda thinking 70/30 shocks etc (all focusing on drag whilst keeping streetability- cruising)

[motorcitydak]

Manual or auto? The manuals will put more of a shock load on the drivetrain when the clutch is dumped while an auto puts a more smooth load on it. If you have an auto in gear with the brakes on and other foot on the throttle, the system already has that force applied. Releasing the brakes just lets it loose.

[G-man]

Manual

4 Speed for now... maybe 1 day a 6 speed viper box (or something that will handle the power)

[six-tee-nine]

Manual

4 Speed for now... maybe 1 day a 6 speed viper box (or something that will handle the power)

Get a dana! and a good driveshaft loop too.....

[Blown70]

I was thinking behind a 528 all alloy hemi. Around 580 hp and the max torque u can get out of it (620+)

a 528 will do those number almost idling....?  Maybe not but that by no means is that high of HP for a 528.....

[Challenger340]

 

It's not that the 8 3/4 Diffys aren't strong enough to Handle exhorbitant power, (they can), it's more a case of assessing the "weakest link", during a "SHOCK LOAD" situation, WITH Traction, in an application.
The 8 3/4 Caps don't like the "shock" of dumping a Clutch,
WHEN,
GOOD Traction is applied, ie; slicks.etc.
or,
the same SHOCK LOAD of a Tranzbrake with Slicks, Traction, etc.

Blows the Caps off the Carrier everytime, if you've got REAL power and TRACTION !

If you are not using Slicks, and don't expect "Track Like" co-efficient of friction on the Tires, even with street sticky's on Road pavement, a properly built 8 3/4" will live just fine without the SHOCK LOAD !

I ran the Car in my avatar at low 10's(4200 elevation), and it still runs today at high 9's (sea level), for "decades", with NO PROBLEMS on the 8 3/4.
Albeit,
the Car "foot launchs" on the Automatic and 4200 stall Convertor, THATS THE DIFFERENCE !

The LOAD was already applied and "stalled" at 3,000 rpm, then, the Foot Brake was released to flash the convertor for the 4200 rpm launch.

Long story short, the "shock" kills the 8 3/4', NOT the Power !

[Mefirst]

I wouldn't say its the "only" the shock that kills a 8 3/4" rearaxel. I think one also need to take into consideration the weight of the car to.. In my op. its a combination of "shock" and weight that kills a 8 3/4" rear...

A 8 3/4" rear can take allot of abuse under a light weight car...

About the weight of the Dana60. IF your running in ProStock then the weight might be an issue, in a mostly street, occasional once a month at the track, ride the added weight of the Dana is nothing to loose sleep over...

/Tom

[BrianShaughnessy]

   The weight difference between the 2 is less than 50 lbs last I recall.    You can buy a aftermarket parts and aluminum center section to try to strengthen a 8 3/4 up some more... and add in axles, etc.    By the time you get done you paid for a dana.    Swap to cal tracs split mono springs and lose the weight and then some.

   I would do a Dana for Black Betty all over again... I'd just call Doctor Diff or Strange first instead of the local friend / chevy guy.    I'm sticking with the 8 3/4 with Sinnamon cause I paid for those F'ing 4.30 gears 30 years ago dammit!   But  I got a couple parts coming my way to help it out some.     

   I'm always disappointed NOT to see a Dana with a chrome cover underneath a mopar.     And I just cringe when I see a ferd 9. 
     

[LeadfootBob]

On a related note, how much will a stock Dana with aftermarket axles take? There's an old Dodge van rotting a few houses over, supposedly has a 60 underneath. I'm a bit tempted to buy it off him, chop the tubes and add mosers/toms/strange/whatever axles to it. Should have 4.10's or 3.54's in it, right?

[62 Max]

Stop and think what was in the Max Wedge / Race Hemi / Altered wheelbase  cars before the Dana came into play in 1966.

[G-man]

I was thinking behind a 528 all alloy hemi. Around 580 hp and the max torque u can get out of it (620+)

a 528 will do those number almost idling....?  Maybe not but that by no means is that high of HP for a 528.....

That is almost idling... running a total mild cam (almost like no cam). This was a suggestion from Ricks Hemis... cause Im not going to the drag strip to have 400 meters worth of room to need the RPM. WIth the mild cam, the power will be lower... which would result in the car accelerating faster for the 1st 100 meters (then the car with the wild cam with high revs would fly by, by this stage). Since my cars gonna be a cruiser with light-light sort of fun/drag there is no 400 meters neccessary so my car ends up quicker by dropping the power closer to 1 and losing top end rpm which I wont use as I wont have a 400 meter stretch where I could have used it as its purely a street car.

So as a street car this mild combo works out quicker than a wild combo... Its also so that I cna drive a fair distance before $$$ goes in the fuel since it is a cruiser... hence the recomended setup.

I hope the information i figured on is correct.

[Challenger340]

Stop and think what was in the Max Wedge / Race Hemi / Altered wheelbase  cars before the Dana came into play in 1966.

Well said !!

[Rolling_Thunder]

run one of the newer / stronger modular 8 3/4 cases in a fabbed housing...   nice and light but also strong...    -  Max wedge cars lived with shitty tapered axle 8 3/4s

[suntech]

Depending on what you are looking for, there are tons of options. I wanted a nice and light as possible one, and went with a Mark Williams Modular. Aluminum complete center, and should be able to hold up against most "normal" builds!!

[Cooter]

It takes an additional 25-35 MORE HP just to turn a Dana 60...



The "Truck" Dana 60, in 3/4 ton version has the EXACT same splines as an 8 3/4" rear's axles...A friend wasn't breaking the 8 3/4, he was twisting the axles at the splines....To me, I don't see the advantage to the larger ring and pinion if the axles are gonna be the next weakest link.....


If it were me, I'd go with the Dana 60, but I'd have some serious 40 Spline or something like it, axles in it...I've seen too many 8 3/4 with huge money in 'em broken with Big blocks and 4 gears...

[FLG]

Is it an auto or manual?? Autos are much easier on the drivetrain.

[G-man]

i said its a Manual Car.

Was just looking for something ot hold up around 600hp and max torque out of a 528ci Hemi (around 2200-6000rpm making over 400)

Drop clutch, slicks grip...

Its not 850+ horsepower... so to me power-weight ratio is what im going for... so the lighter I can get the car the better (without going to fibreglass panels).

I asked a place that does differentials and they told me not to bother with the truck diff (dana 60) too heavy and a propperly built 8 3/4 with alloy components will weigh much less and be as  strong, more than strong enough to handle that power even at a drag strip.

Im not going a wild build... as the cars not going racing. Its gonna have a mild build so that the powers closer to 0. That should in turn make it slightly faster in the 1st 100 meters (power band closer to 0) ad then ofcourse not as quick over an actual quarter as the wild cam car... but i aint going race where theres gonna be 400 meters... hence the idea of mild.... makes it the fastest for street application and much more efficient to.

Manual Gearbox...

If I ever get to do the gearbox I want, it will be a sequential 5 or 6 speed with a 395 9 (5 speed) 410 (6 speed). But then again considering the mild setup... and power being so low... maybe the 395s is useless and therefor a 323 or 354 is better... Vipers are fast as hell in acceleration and there 2:8... so i dunno. THats where i get all confused.

[FLG]

I dont see an 8 3/4 coupled with a manual tranny a 600hp monster, and dead hooking with slicks lasting very long IMO.

Dr.Diff sells complete danas ready to be bolted in

http://www.doctordiff.com/?page_id=5

Expensive but its bolt on ready to go so you cant complain.

I say better be safe then sorry. If the 8 3/4 breaks your now looking at the lost money on that and having to build a Dana.

[G-man]

Well what on earth do drag cars run... Dana 60s also?

I mean they run over 1000 HP (those cars)....

[FLG]

Im no expert just going by what ive been told and heard.

Id ask Firefighter Ron or even call Cass (Dr.Diff) and see what he says.

You need to remember alot of those cars are using shortend rears (which are stronger).

[Charger-Bodie]

Well what on earth do drag cars run... Dana 60s also?

I mean they run over 1000 HP (those cars)....

Most Drag cars that dont want a broken rear run a Dana60.....Thats what the Charger Im building will have and what the one I just sold had too............Nothing can compare to the strength of a Dana.

[G-man]

When the diff goes in its going in with 15x12 Wheels on back with 15x15 pro street hoosiers (radials)... if I ever want to I can still run a 15 or so Hoosier D.O.T slick on a 15x12 also. (keeps it looking good and still available slick sizes to run on that size also if I ever want to run a DOT one time) that also means it has to be shortened as a mini tub would be neccessary.

But to me, weight saving is what im after... If a dana can handle say even 2000+ horsepower... well im not running even close to that, so isnt in that sense a dana 60 over kill. Im just trying to handle 600 not 1000+.

I know looks wise the dana is  but howmuch heavier is it... these people made it out like 100kg (220 lbs) or something.

[Blown70]

well the 8 3/4 would handle the 600, after that I would not want one myself.  Others opinions may vary.  I do the think the dana 60 is 220lbs MORE than 8 3/4 mabe 40 to 50, I think that was mentioned here or another thread. 

The dana in my car I was told could handle 1500HP without issue for sure..... I may test that one day....

[Cooter]

One thing to remember G-man, ALOT of times, the car is driven harder on the street than at the track (At least that's how it is round here)..

IF your gonna be beatin' on it (IE: Dumping clutch, Bang/screech shifting, etc.) Go with what will most likely stay under there Dana 60...

We ran one of those TKO Tremec 3550 Trans' in a mustang, and only got about 9 passes out of it before it gave up (650 ft. lbs, 393 Windsor)..
Ended up calling the rep and he told us it wouldn't live very long in a "Race" atmosphere...

[G-man]

Hi George,

The torque and weight of your car will break any 8 3/4" if the car hooks up
under hard acceleration.

Narrowed truck Dana 60 rears are heavy 

I recommend a NEW Dana 60 assembly, 
built with a lightweight casting and 1/4" wall DOM axle tubes.  It only
weighs 40 lbs more than an 8 3/4". 

Thanks DrDiff

[FLG]

There ya go 

[Cooter]

I expect this will change when and If I go back to a 4 gear in my Dart, but I've run 6.80's with a 505 C.I. stroker with 727 4000 Stall DOT tires, with a 180 60 ft. On an 8 3/4 with 3.91 gears and stock shortened axles...Course, Knock on wood, It could break tomorrow too....

[69charger440]

Well there is a reason chrysler put the Dana 60 in the 440 and 426 hemi four speed cars. They simply hold to torque without breaking. Plus as mentioned you are going to have the power of the engine plus the wiegh of the car fighting the rearend until you start moving foward. Plus, a Dana 60 cant hurt the value of the car any. Just my opinion.

[G-man]

Well there is a reason chrysler put the Dana 60 in the 440 and 426 hemi four speed cars. They simply hold to torque without breaking. Plus as mentioned you are going to have the power of the engine plus the wiegh of the car fighting the rearend until you start moving foward. Plus, a Dana 60 cant hurt the value of the car any. Just my opinion.

It will hurt value... make it worth more 

Did i mention they look way nicer under there? 

[62 Max]

Well there is a reason chrysler put the Dana 60 in the 440 and 426 hemi four speed cars. They simply hold to torque without breaking. Plus as mentioned you are going to have the power of the engine plus the wiegh of the car fighting the rearend until you start moving foward. Plus, a Dana 60 cant hurt the value of the car any. Just my opinion.

Well,I'll say it again!

Stop and think what was in the Max Wedge / Race Hemi / Altered wheelbase  cars before the Dana came into play in 1966. 

[69charger440]

you make a good point. It is your car. I was struggling with this also and i happen to come across a dana at a cheap price. What ever you choose i hope it works well for you. I am sure both will work if done right. Good luck

[G-man]

Well there is a reason chrysler put the Dana 60 in the 440 and 426 hemi four speed cars. They simply hold to torque without breaking. Plus as mentioned you are going to have the power of the engine plus the wiegh of the car fighting the rearend until you start moving foward. Plus, a Dana 60 cant hurt the value of the car any. Just my opinion.

Well,I'll say it again!

Stop and think what was in the Max Wedge / Race Hemi / Altered wheelbase  cars before the Dana came into play in 1966. 

I got no clue what was in them, how heavy they were, howmuch power went through them, how long did they last. I have NO idea so its hard to think what was in them.

Please elaborate in detail

[62 Max]

Well there is a reason chrysler put the Dana 60 in the 440 and 426 hemi four speed cars. They simply hold to torque without breaking. Plus as mentioned you are going to have the power of the engine plus the wiegh of the car fighting the rearend until you start moving foward. Plus, a Dana 60 cant hurt the value of the car any. Just my opinion.

Well,I'll say it again!

Stop and think what was in the Max Wedge / Race Hemi / Altered wheelbase  cars before the Dana came into play in 1966. 

I got no clue what was in them, how heavy they were, howmuch power went through them, how long did they last. I have NO idea so its hard to think what was in them.

Please elaborate in detail

All were 8 3/4 rear,tapered axle from 62/64 then flange in 65.
Take some time and read this.
http://board.moparts.org/ubbthreads/showflat.php?Number=3257129

[G-man]

Thanks

I read it all... didnt really say anything to do with how long they lasted or anything, just gave 'this car ran 12 seconds, street cars etc etc'

Dunno, maybe it was wrong link?

But heres another I got from DrDiff when I asked about the old 64 Hemi cars etc.

Stock stroke, lightweight, automatic cars can run 8 3/4" rears.  '60s top
fuel dragsters also used 8 3/4" rearends. 

Torque, traction and weight will break 8 3/4" rears regardless of the 1/4
mile ET, however.  For example, my friend's 383/4 speed SuperBee was fine
until he swapped in a 440.  After that, the 12 second car couldn't make 1
pass without breaking the 8 3/4 rear.  After 2 sets of axles and 2
third-members, I built him a Dana 60.  No more problems.

Cass

[maxwellwedge]

I ran an 8-3/4, 4.30 gears, Auto, 4800 stall 685 Horse 440 Challenger with 10" slicks (and stock axles) many years at the strip with no problems. I was probably lucky with the stock axles but I never heard a whimper out of that rear end. Got near 11.00 flat et's before I sold the car.

[G-man]

I ran an 8-3/4, 4.30 gears, Auto, 4800 stall 685 Horse 440 Challenger with 10" slicks (and stock axles) many years at the strip with no problems. I was probably lucky with the stock axles but I never heard a whimper out of that rear end. Got near 11.00 flat et's before I sold the car.

Probbably because it wasnt a Manual car that shocks it more so.