Which is stronger

[ronw]

Just curious, if you were building a rear by narrowing it and putting together the gears would you use an 8.75 or a 9.25? Which would be stronger? Or which would you choose and why? I just happened to have the parts for both. Thanks Ron

 

[super-bee_ski]

Definitely in my opinion: the DANA 60

But, many "street cars with in excess of 500HP run the 8:3/4
Built up of course.

I suppose Mike Gaines can give you some info.
He just upgraded in September I think...
send him a PM

 

[Budnicks]

IMO
Never been a big fan of using the 9.25" for a performance build,
the 8.75" has it's limitations too, on a 500hp automatic it will do well,
set up correctly, with a 4 speed, or slicks & hard launches a little less longevity...
Depending on what carrier & pinion sizes
carriers #'s 741 smallest/weakest,
larger pinion 742 non tapered is decent {I've had good luck}
slightly larger tapered pinion 489 "allegedly" the best
{I didn't have any better wear or tear with them over the 742 carrier thou}...
I've had good luck with a few of them {8.750" 742 rears} with power far exceeding
the 500hp {well over 700hp+ 300 shot of N20} mark too...

Had a 742 case in a 23 T Altered only weighed 1800#'s with a
1800hp Blown alcohol combo & a clutch-flite, Lenco pieces/axles/spool, no suspension/solid
trussed housing etc. back in the day, it lasted the life of the car, 10+ years, 12+ races a yea.
no breakages at all, but I was going for lightest I could...

BUT IMO by the time you spend the money to make a inferior rear end hold up,
you could probably have a 9.750" Dana 60 or a all new S-60 from Strange Engineering...

a 9.750" Dana 60 {or S-60} is the best

anyway good luck

 

[Mike Gaines]

Picture above is of my new Dana 60.
IMO less than 500hp an 8 3/4 should be ok for a street car with just a little drag racing action...but like everyone will tell you...if you are starting from scratch...do a Dana 60.
Find suitable donor for the Dana 60 housing from a junk yard and then have a rear end fabrication shop narrow that housing, order the correct length axles and your choice of gear ratio and differential (posi unit).
You can use your drum brakes off your current setup if you dont want to spend the money for disc brakes on the rear.
My entire setup cost about $2900, TURNKEY, installed with Narrowed Donor housing, all new brake lines, etc.... and all Moser parts.
I just dropped the car off at their shop along with the Dana Donor Housing...then about a week later I picked up the car...100 per cent finished....now, of course, I have the rear end they took out of the car for sale...the narrowed 8 3/4 with 742 case, Detroit Locker Differential, Strange Axles and 4.10 gears...all for sale for only $995 complete, ready to drop in using your brakes and springs.
I did not make even 1 run with the 8 3/4 housing in the car after I installed my new 505" stroker motor. Didn't want to break the 8 3/4.

 

[snakeoil24]

Get yourself a dana 60 and put big Ford Wheel bearings with new ends on it. This will give you the 9 3/4 gear plus the larger end bearings used on 9 inch Ford Rears. Nothing will come close to this combo.

 

[hangn0ut]

9 1/4 or 8 3/4? The 9 1/4 might be stronger simply because its larger. However parts availability may be the deciding factor. Do you have a sure grip carrier? Gear set you want to run? Better find out where or if they are available. Housing ends and axles shouldnt be a problem but what about bearings? 9 1/4 has c clip axles. Not desireable. Is a green style bearing availble? These things can stop a project dead in its tracks. 8 3/4 has none of these questions. Plus drop out 3rd members are nice to work with compared to carrier tube axles. 8 3/4 is the way to go. But if you decide otherwise I got a nice cast aluminum cover I'll sell to ya cheap.

 

[cryplydog]

All good advice from above but I agree with Bud on the strange S-60, you can get it any way you want it and at a GREAT price. I really don't think you can buy used components and set one up to your Dims. for the same money even if you did it yourself. good luck

 

[HEMI-ITIS]

Still have the Dana with a spool that came in my when I bought it 28 years ago.I'm throwing north of 850 ft lbs of torque at it,,,,,,,and it wants MORE!

 

[super-bee_ski]

It's conclusive
Go Big!
Go DANA!

 

[GITEX]

Yup Yup ^^^^^^
Strange Dana

 

[Homstead]

I agree! For shear brute strength the Dana is the way to go although 8 3/4 are pretty strong too. If my only choice was between the 9 1/4 and the 8 3/4 I would chose the 8 3/4. It has more going for it.....

 

[HEMI-ITIS]

I agree! For shear brute strength the Dana is the way to go although 8 3/4 are pretty strong too. If my only choice was between the 9 1/4 and the 8 3/4 I would chose the 8 3/4. It has more going for it.....

Please tell us how the 8.75 has more going for it than the Dana 60.

 

[hangn0ut]

Hes not talking 60 but 9 1/4 vs 8 3/4 because thats what OP asked about. And those are the rearends he has. 60s are it as far as no worries fun is concerned. The one in my dart hasnt had a single problem since i put it in about 1983. Same gearset since bout 85. 4 series carrier,4.88 richmond. They are getting loose though.

 

[HEMI-ITIS]

Hes not talking 60 but 9 1/4 vs 8 3/4 because thats what OP asked about. And those are the rearends he has. 60s are it as far as no worries fun is concerned. The one in my dart hasnt had a single problem since i put it in about 1983. Same gearset since bout 85. 4 series carrier,4.88 richmond. They are getting loose though.

See what happenz when ya get old?? I did think he was referring to the 60,my apoligies:eusa_silenced:

 

[Homstead]

See what happenz when ya get old?? I did think he was referring to the 60,my apoligies:eusa_silenced:

See what happens when you forget to put your glasses on? lol

 

[cryplydog]

Mopar Action magazine had a great layout with details on which bodys to source a 9-1/4 and the mods. to turn it into a great street/strip rear end using all common parts for them. Some machining involved. Richard Erinberg wrote a top notch article and would be a valid and useful pc. if looking for something between a 8-3/4 and the 9-3/4 dana. Its a good read but still a lot of time money work involved but Ebooger is a great penny pincher which is important to a lot of enthusiasts out there.

 

[nuteguy]

cryplydog, do you happen to have a link to that? not to hijack the thread but i have a 9.25 posi with 3.55s available to me for an unbeatable price which would be an upgrade from my 8.25 with 2.73 gears (i know its 2.7 something. not sure about the 3). what isn't going for the 9.25 besides parts availability?

 

[Cranky]

With the 8 3/4, it's not so much as which one is the weakest of the 3 (measure the Dana 60 pinion vs the 741) but when will the teeth shave off of the ring gear? Also look at the size of the carriers from the 8 3/4 vs the Dana 60. Does the 9 1/4 even have a Power Lok Sure Grip or is it the lowly Track Lok? The Track Lok.....well, you can keep that great piece of art work. Here's the difference between the 8 3/4 and the Dana 60 Power Lok carriers....

 

[Bb70charger500]

I would lean more towards the bigger 8 3/4 as there tough as nails a lot cheaper to build if you blow it to hellyou can easily get another just about anywhere and you can drop the chunk out quickly if needed (at the race track)
Good luck ether way

I was going to buy a Dana for my charger but decided there was to much negative and didn't make sense my car will be making a tad under 500 rear wheel hp I need to tune it down a little

 

[cryplydog]

cryplydog, do you happen to have a link to that? not to hijack the thread but i have a 9.25 posi with 3.55s available to me for an unbeatable price which would be an upgrade from my 8.25 with 2.73 gears (i know its 2.7 something. not sure about the 3). what isn't going for the 9.25 besides parts availability?

Nuteguy, go to moparaction.com, June,2012 vol. 19. The article is called.....Revolution#9-1/4. I think they have back issues but you might find it on the web. Sounds like you have the hard parts. good luck