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8 3/4 axle twisted

Posted By: Wedgeman

8 3/4 axle twisted - 10/11/13 07:50 PM

With the new engine in my 67 Barracuda, I went to track and twisted the housing. The 408 dynoed 606hp at 6300rpm and 553 lbs at 5100 rpm.

The housing gave up, so there are 3 options for me:

1-Change the housing and brace it with the mopar brace

2-Go with a Moser axle housing cut to length

3-Go with a Dana 60

I already have 35 spline spool and axles

What would be my best option for reasonable price ? Any ideas welcome............
I'm running ladder bars

Dan

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Posted By: 451Cuda

Re: 8 3/4 axle twisted - 10/11/13 08:08 PM

Either Moser housing or brace another stock one, depending on what you want to spend. Braced stock one one would live fine IMO.
Posted By: Polarapete

Re: 8 3/4 axle twisted - 10/11/13 08:11 PM

I would recommend the Dana 60 solution. You should be able to reuse your 35 spline axles and brakes. Truck Dana housings are easy to find for less than $200.00. Make sure the side carrier bearing has not spun in the housing to avoid additional machining costs (common problem, easily fixed). You will need to buy a new spool, bearings, seals, gears, companion flange, housing ends, ladder bar mounts, and shorten the driveshaft, but altogether (with your existing axles and brakes) you should be able to permanently solve your rear end troubles for less than $1,000.00. Check with Dr. Diff on prices. And you could sell the 8&3/4 carrier and spool to make up for a lot of the difference. And once you have a bullet-proof rear end, you can almost forget about the major reason that 727s explode.
Posted By: cudasteve68

Re: 8 3/4 axle twisted - 10/11/13 10:17 PM

I run a braced 8-3/4" in my junk. I do not run a transbrake. Best 60' 1.42, normally 1.45. I made the brace myself from a piece 6.0" X 2.0" X 1/8" RETU along with a little help the tube laser at work. I have never had any issues. However I do not think I would run a brake with that set up.

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Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/11/13 10:45 PM

Hummmmmmmmmmm........
Posted By: Whompin_Wedge

Re: 8 3/4 axle twisted - 10/11/13 10:51 PM

Quote:

I would recommend the Dana 60 solution. You should be able to reuse your 35 spline axles and brakes. Truck Dana housings are easy to find for less than $200.00. Make sure the side carrier bearing has not spun in the housing to avoid additional machining costs (common problem, easily fixed). You will need to buy a new spool, bearings, seals, gears, companion flange, housing ends, ladder bar mounts, and shorten the driveshaft, but altogether (with your existing axles and brakes) you should be able to permanently solve your rear end troubles for less than $1,000.00. Check with Dr. Diff on prices. And you could sell the 8&3/4 carrier and spool to make up for a lot of the difference. And once you have a bullet-proof rear end, you can almost forget about the major reason that 727s explode.



This

We run this same set-up, 30 spline axles even. We have been 1.28 60ft (no transbrake) and our rearend troubles are gone. We twisted a backbraced 8 3/4 and broke multiple pumpkins which led to broken sprags.. Once you add more power you will be glad you went dana..

Casey
Posted By: 70dusterjohn

Re: 8 3/4 axle twisted - 10/11/13 11:00 PM

I agree with the Dana, best thing I did ! Don't get me wrong we ran the 8 3/4 back braced spool axles and didn't break but I was worried ! Weight kills them ! If you can sell off what you have and get the Dana !
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/11/13 11:12 PM

And from what model truck should I get a cheap housing and best supplier for parts ?
I take it the Dana from trucks are sufficient ?
Dan
Posted By: kingdust

Re: 8 3/4 axle twisted - 10/11/13 11:20 PM

I would not put any money into an 8.75! Dana or 9". If you ever upgrade to a higher HP engine the Dana or 9" will hold up. The rear is one part that overkill is good.
Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/11/13 11:32 PM

Quote:

And from what model truck should I get a cheap housing and best supplier for parts ?
I take it the Dana from trucks are sufficient ?
Dan

If you can find a truck or van dana 60 housing that has the three (3.0) diameter axle tubes buy it quick take your time looking, if you can't find one of those then look at buying the next size axle tubes that are 3 1/8, some are even 3 1/4 diameter , I would stay away from them BTW some fo the GM and GMC early(1970 and earlier ) 3/4 ton pickups had those and I think even some of the early Dodge and Ford pickups had them also. I'm not exactly sure when Dana Corp. started making the Dana 60 with 3 1/8 axle tubes
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/11/13 11:38 PM

Will I be able to retain my 35 splines axles from my 8 3/4 ?
Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/12/13 12:04 AM

Quote:

Will I be able to retain my 35 splines axles from my 8 3/4 ?

I had Strange 35 spline race axles special made to work with the stock A body 8 3/4 housing with the strange 35 spline 8 3/4 spool, I twisted that rascal(houusing) up horribly with no back brace. I swapped the axles over to the truck Dana 60 I had narrowed and I had to cut about 3/8 inch off the end of one axle, so yes you can reuse your 35 Spline axles in the Dana 60 with the 35 spline Strange, Dutchmen, Yukon and many other spools Make sure and check for end play, don't let the axles butt in the center The exception might be the Mark Williams 35 spline spool with thier different axle and spool teeth angle, 30 degree versus maybe 45 degree angles, not sure which one is which
Posted By: Whompin_Wedge

Re: 8 3/4 axle twisted - 10/12/13 12:05 AM

Yes you can, you have to put 8 3/4 ends on the dana. Brakes will work too.

Casey
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/12/13 12:13 AM

Quote:

Yes you can, you have to put 8 3/4 ends on the dana. Brakes will work too.

Casey


Duh !! of course it will fit ! loll haven't thought of that so far lollll

Cab burge is saying my spool will fit in a Dana ???
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/12/13 12:23 AM

After that, will I need to brace the housing or special welding to the Dana ?
Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/12/13 12:25 AM

Quote:

Quote:

Yes you can, you have to put 8 3/4 ends on the dana. Brakes will work too.

Casey


Duh !! of course it will fit ! loll haven't thought of that so far lollll

Cab burge is saying my spool will fit in a Dana ???

NO Not even close, sorry But your 35 spline axles (brakes and brake drums will fit on the new ends also) in most 35 spline spools BTW, make sure and mark your axles(right and left) when you take them out of the 8 3/4 and put them in the new cut down Dana 60 on the same side thay came out of so you don't try and run them backwards to what they've been run already
Posted By: Whompin_Wedge

Re: 8 3/4 axle twisted - 10/12/13 12:26 AM

I believe we had to change spools..

But there is no need to backbrace the dana

Casey
Posted By: DusterKid

Re: 8 3/4 axle twisted - 10/12/13 12:48 AM

put a dana in it and forget about having issues with your rear...
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/12/13 12:51 AM

convincing enough...........!
Posted By: fourgearsavoy

Re: 8 3/4 axle twisted - 10/12/13 12:53 AM

I have Moser 35 spline 8 3/4 axles in my Dana 60 with a Moser spool with no issues at all
Gus

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Posted By: mr. 63plymouth

Re: 8 3/4 axle twisted - 10/12/13 06:39 AM

Hi,
I would just brace a stock 8 3/4" housing and keep racing!
I run a 68 barracuda with a braced 8 3/4" housing and ALum. Centre section, and really good gun drilled 28spline axles and run mid nines with no trans brake and never had issues, plus the car 60's in the mid/low 1.30's!!
If I were you I wouldn't go the Dana way, those are for tanks!!
When you put your new diff in(whatever you go with) make sure you get a 4 wheel alignment, that's probably more your issue why your diff went south!!
Just my two cense!!

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Posted By: rustbuckett68

Re: 8 3/4 axle twisted - 10/12/13 05:32 PM

Some Ford 1/2Ts from about 64 -72(?) used the Dana 60 when a locking axle was ordered. I have a 69-70 D60 in my 66 F-100, but can't remember the specs (tube diameter, width). My 69 Fargo service manual shows 5 bolt D60s, but I can't remember if I've ever seen one.
Posted By: perfmachst

Re: 8 3/4 axle twisted - 10/12/13 05:44 PM

hi, the 1967 to 72 ford 1/2 ton pickups had dana 60 rearends. it has 3 " tubes, is the lightest housing. cut ends of and weld on mopar ends
I put one in a duster with fourspeed, its never givin me any trouble.
I had to buy a spool, gears and yoke to make it fit. very simple change over. also, it has passenger car ends.with flanged axles.
Posted By: Darryls-Demon

Re: 8 3/4 axle twisted - 10/12/13 06:17 PM

The 8 3/4 Moser fab housing is a nice piece BUT they are a pain in a A-body with a stock fuel tank and fuel lines, everything is very tight.
Also if you have the tubes braced on the Moser you will need to have the braces notched so the shocks fit.

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Posted By: SpareParts

Re: 8 3/4 axle twisted - 10/12/13 06:58 PM

I was in your shoes last fall OP, I spent a day with my housing in a press and checked it with a jig then I built a tubular back brace and a smaller diameter tube under the housing that ties the pumpkin to my boxed in spring perches. This thing is STRONG!!!! Then you can get after it and tune that chassis
Posted By: racerx

Re: 8 3/4 axle twisted - 10/12/13 07:16 PM

Quote:

The 8 3/4 Moser fab housing is a nice piece BUT they are a pain in a A-body with a stock fuel tank and fuel lines, everything is very tight.
Also if you have the tubes braced on the Moser you will need to have the braces notched so the shocks fit.

That's what i use

if u were closer i'll buy that center sec.
Posted By: 72Swinger

Re: 8 3/4 axle twisted - 10/12/13 07:33 PM

Strange S-60 housing $569.
Posted By: DoctorDiff

Re: 8 3/4 axle twisted - 10/12/13 09:52 PM

$1800 will buy a new, bolt in S-60 Dana 60 assembly built with 1350 yoke, 35 spline race axles and a spool.

It weighs about the same as a comparable 9" rear, but costs less and consumes less HP.
Posted By: jcc

Re: 8 3/4 axle twisted - 10/12/13 10:16 PM

Quote:

8 3/4" housing and ALum. Centre section, and really good gun drilled 28spline axles and run mid nines



Sorry OT, I'd love to know more details on your "gun drilled axles"
Posted By: kingdust

Re: 8 3/4 axle twisted - 10/13/13 12:30 AM

Quote:

put a dana in it and forget about having issues with your rear...

I put a 9" in my car only because I can swap out the carrier at the track if I have to and parts are easy to get. again I wouldn't sink money into an 8.75 with anything over 450hp and definitely not with a stick car!
Posted By: fourgearsavoy

Re: 8 3/4 axle twisted - 10/13/13 01:06 AM

Quote:

Quote:

8 3/4" housing and ALum. Centre section, and really good gun drilled 28spline axles and run mid nines



Sorry OT, I'd love to know more details on your "gun drilled axles"


Me too why would you drill a 28 spline axle
Gus

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Posted By: mr. 63plymouth

Re: 8 3/4 axle twisted - 10/13/13 07:37 AM

Hi,
My whole car is all weight revolved!! So I ordered mark Williams 28 spline good axles and had them machine out then heat treated!! Plus ring gear is cut back for weight!Killer strong and could put any centre section gear swap in anytime! Run a Detroit locker as well, no spool. Car is a true street car!
Helps that I have a good friend that does this kinda stuff!!
All steal body with stock glass, but sneaky lighting parts to make the car lighter, but look stock!!
Lol, it's just me!!!
Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/13/13 07:46 AM

Quote:

Hi,
My whole car is all weight revolved!! So I ordered mark Williams 28 spline good axles and had them machine out then heat treated!! Plus ring gear is cut back for weight!Killer strong and could put any centre section gear swap in anytime! Run a Detroit locker as well, no spool. Car is a true street car!
Helps that I have a good friend that does this kinda stuff!!
All steal body with stock glass, but sneaky lighting parts to make the car lighter, but look stock!!
Lol, it's just me!!!

I've never heard of any 28 spline Mopar axles for 8 3/4, let alone a 28 spline spool for the Mopar 8 3/4. Ford nine inch yes, but not Mopar 8 3/4 Your not a keyboard racer, car builder are you
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/13/13 04:18 PM

I went with a Dana.....
With the engine dynoed at 606hp, I''ll be sure it won't happen again !

If I add a 200hp shot of nitrous, that will be a killer on the 8 3/4 for sure.

I won't go there again
Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/13/13 06:02 PM

Quote:

I went with a Dana.....
With the engine dynoed at 606hp, I''ll be sure it won't happen again !

If I add a 200hp shot of nitrous, that will be a killer on the 8 3/4 for sure.

I won't go there again

Good choice
Posted By: Wedgeman

Re: 8 3/4 axle twisted - 10/13/13 06:36 PM

Can someone explain the differences between 2-series and 3-series gears ?

Hope I won't run into any problems putting a spool and 4.56 gear !
Posted By: Polarapete

Re: 8 3/4 axle twisted - 10/13/13 07:38 PM

The difference is in the thickness of the ring gear. You will need to specify the ratio to the spool vendor, so that you get the right one. In the old days, we used a spacer with the stock PowerLock carrier to space the truck (4.88) gears closer to the pinion center line. A weak solution as eventually the longer ring gear bolts would loosen and cause mischief. But then we also used OEM axles and they began to show twisting signs
Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/13/13 08:02 PM

Quote:

Can someone explain the differences between 2-series and 3-series gears ?

Hope I won't run into any problems putting a spool and 4.56 gear !

Dana 60 never came with a two sereis gear, only down to 3:54.The Dana 61 came with 3.30 gears. The two most common Dana 60 carriers and spools are three series or four sereis, the three sereis works on 3:54 to 4:10 stock Dana brand gears and on the U.S.(Strange house brand also)4:30 ratio. The four sereis works on 4:56 and above on most Dana gears and most after market gear sets, not all though When it comes time for you to buy a spool and gears make sure they are matched (same manufacturer if possible or same vendor )and intended to be ran with each other I just went through the hassle of trying to find out what U.S. Gears, 4:30 ratio, fit on which sereis 40 spline spool U.S Gear reps didn't know, U.S. Engr. didn't know They said to call Strange, Strange had already told me to call U.S. Gears I ended up calling a guy in Montana that use to own a rear end shop(J&S) in SO CA years ago and he said that the U.S. 4:30 gear sets will only fit the 4 sereis 40 spline Moser spools I bought a new one(40 spline steel spool) but I haven't swapped the 5:13 and Mark Willaims aluminum five seresi spool out of my new race car yet for the 4:30 and new steel spool, so I'm hoping he's correct IHTHs
Posted By: mr. 63plymouth

Re: 8 3/4 axle twisted - 10/14/13 04:44 AM

Sorry,
my mistake meant to say 30spline axles!

Posted By: Cab_Burge

Re: 8 3/4 axle twisted - 10/14/13 04:48 AM

Quote:

Sorry,
my mistake meant to say 30spline axles!



I thought maybe you might be confusing the Ford nine inch parts with the 8 3/4 parts
Posted By: SoCalRacer

Re: 8 3/4 axle twisted - 03/19/14 10:49 PM

Late reply, as usual

Did the same thing to the 8-3/4 in my all steel '70 'Cuda with a 340; although a stick car. Put in a Dana 60 and never looked back. That was in 1985, and still running high tens today with no problems! I was bucks down back then and took a semi-floating truck housing, cut the ends off (since I was narrowing anyway) and welded on the ones from the twisted 8-3/4. I did build an alignment fixture to get the ends centered correctly. Running a spool and 35 spline axles... pretty close to bulletproof.
Posted By: dogdays

Re: 8 3/4 axle twisted - 03/19/14 11:08 PM

Gun-drilled axles save weight with nearly no decrease in strength, either torsional or in bending. The inner material is just along for the ride, it is so close to the neutral axis that it doesn't do anything when the axle is stressed. Strength goes up as the third power of the diameter, IIRC.

R.
Posted By: dvw

Re: 8 3/4 axle twisted - 03/19/14 11:13 PM

Quote:

Will I be able to retain my 35 splines axles from my 8 3/4 ?


You will be able to use the old axles. But you will have to narrow the new housing about 1" narrower. The Dana pinion is offset. A Dana has one axle longer than the other. The shaft splines are long enough to slide the axle through the spool, no need to cut it off. So when you set it up, make the housing cut so the long axle side uses your existing axle length. The Pinion offset will result in the other side being shorter. Thus the shorter housing.
Doug
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