BIG blocks and 8 3/4 dont go, lol

Was at a www.abodyjoe.com (http://www.abodyjoe.com) member track rental monday and was making my best pass ever when.......
http://i192.photobucket.com/albums/z5/thelegendTim/trackandgeaRS004.jpg
http://i192.photobucket.com/albums/z5/thelegendTim/trackandgeaRS006.jpg

http://lh4.ggpht.com/cudadan360/SNfcj7flssI/AAAAAAAAAcQ/CT_0Aiy2Vqg/s512/DSC_0104.jpgthanks to fastmetal for the wheels up pic......STREET TIRES +STOCK SUSPENTION

What do you think happened?

Traction and horsepower will do that.

Don't they make billet 8-3/4 caps?

Strange does, and others might. That must have hurt. Hope you get it fixed soon.
Alan627b

Now would be a perfect time for a DANA 60 upgrade!!

Looks like you are really hooking up with all the air under the front end.

Sorry your going to be down for awhile... that bites.

I guess you've found the weakest link in your setup.

The weird thing is it broke 100' before the finish line! Was making a killer pass too !
Even a billet capped 8 3/4 will not stand up to that much power,plus if I am going to spend over $800 to put caps and gears into my unit and then always worry about it I might as well just add another $1000 a dont ever worry about the rear again.... DANA !!

Now would be a perfect time for a DANA 60 upgrade!!

Looks like you are really hooking up with all the air under the front end.

Sorry your going to be down for awhile... that bites.

Dana yes !!
not bad for s.s springs and STREET tires,huh !
2 weeks top's ,I can't go any longer with out my cruising fix ...8)

I've got billet caps in mine. No problems. The caps are the weak link on the 8.75.

Moser has a 3 day turn around on a dana 60 ... callem up and it will be at your door in less than 7 days ..

First question is how much power and torque was being use on the car.2)if you are using over 500hp and torque,and think you can run stock caps at a drag strip,its your own damm fault.3)After market caps are CHEAP insurrance to failures like this.4)Who set up the gears? There is nothing wrong with having a 8.75 diff behind a BIG BLOCK or hemi and making it last,did it for years and never a problem.This is more of a set problem than a cap failure,mrmopartech

well 8 3/4 rears can be fine behind a big block. but that thing of yours is a monster.. :)



http://www.youtube.com/watch?v=VMWQ83xj6Pg

my dart has a .30 over 440.eagle rods, ross dome 14.5.1 forged pistons,floating pins, ultradyne .284 dur. and .691 lift roller cam and comp roller lifters. m1 intake ported heads they flowed .296.we are figuring around 720hp or so.maybe alittle more. have a friend in a 3600lbs cuda with driver that just ran a 10.22 at monster mopar weekend with wheels up then spinning. thinks he can squeaze a 10 flat. i am weighing about 3000 lbs with driver. i am running foot brake w/4800 stall and 4.30 spooled with 8.75 and a rear axle housing brace. will this work mr.mopartech?

After you fix the caps the ring teethe become the next week link. theres no fix for that.

mr.mopartech, WELL OVER 800hp and the only thing on that car I didn't touch was the rear,was told it had caps,guess not lol

nice video Abodyjoe ! wish mine went like that !!! LOL

Tim

10sec340,

Mark Williams makes the billet steel caps, and billet adjusters. I've seen the oem adjusters blow out, also. Like Adam said, the next weak link is the small diameter ring gear. And not to mention the flimsy 8.75" housing (ring gear deflection).

I've built both 8 3/4" rears and danas for drag cars with big blocks and trans-brakes. You can be on the fence real easy. Losta power like you make, and the heavier cars are brutal on the 8 3/4" rear.

FWIW, my red b'cuda went 10.00 @ 130 with an 8.75" rear. It weighed 3025, with 500cid, and a brake. I used the MP aluminum 3rd member, and backbraced the housing.

Now, I deal with this all the time with my customer's when they break their 8.75. By the time it's all said and done I could of bought a complete dana 60 with disc brakes and had money left over vs. modifing the 8.75". More times than not, we upgrade them to the dana!

Good luck getting it fixed, and goodluck with your racing!

My only question is if you are going to chrome that bad boy and hang it over the fireplace....

Rev.

I wonder if the ring gear let go before the cap did.

I wonder if the ring gear let go before the cap did.
from the look of it and the way it drove out of the explosion I would guess the cap broke first.

Tim

im a firm believer in the dana.

After you fix the caps the ring teethe become the next week link. theres no fix for that.
yes there is;better gears. the company that makes gears uses the same steel for all gears so if the grears break they break in any rear. The trick to a 8 3/4 is good parts and setup. the picture of the broken rear looks to me he has a spring pos in it.How long did it last befor it broke, what case was he using and most of all was it setup right.the video I seen if the 8 3/4 had the correct on it could handle all that car could give it.There aer three differant 8 3/4 rears don,t condemn 8 3/4s when you are using the wrong one or the wrong parts.

Wow...i love my 8 3/4's but i think its time for you to step up to a dana...

Welcome aboard dartcuda1. What would be the 8-3/4 to use and what upgrade parts along with it? Minus the aluminum center section.

well the new 489, with strang spool,M/W Billet Caps and richmond Pro gears seem to be holding up to a few hard passes! well see !!!!!!!! moser axles didn't even get a nick in them :)

The old one had many many street miles and pass's on them before it went,so yes it was set up right just weak caps finally went bye bye,also that was by far the best pass(60' and 1/8 ) when it let go, It was also the first time I went ALL OUT HARD on her !

Hey Tim, sounds like the right parts in there now. For surely the "Pro Gears" from Richmond will add life. Not like them hard ass street gears.

Hey Rumble

testing on sunrise saturday,come down ! also going to Atco Monday,have a rental, come down for that to..... going to give the rear a good amount of abuse....... we'll see !!

We'll see what the weather brings. What time?
ATCO is out of the question though.
Make sure somebody gets video of it all.

http://bbdart.com/mycar/DanaVS875.jpg

looky looky , broken gear and non broken caps .

The teeth on he gear are the weakest link .

yes there is;better gears. the company that makes gears uses the same steel for all gears so if the grears break they break in any rear. The trick to a 8 3/4 is good parts and setup. the picture of the broken rear looks to me he has a spring pos in it.How long did it last befor it broke, what case was he using and most of all was it setup right.the video I seen if the 8 3/4 had the correct on it could handle all that car could give it.There aer three differant 8 3/4 rears don,t condemn 8 3/4s when you are using the wrong one or the wrong parts.

No shit , who ever is responsible for putting that piece of crap CONE TYPE in there needs their head examined .

It looks to me (looking at the the that are not broken... that the ring gear failed first. The wear surface of the teeth look like crap. I'd bet the teeth broke after getting hot at the end of the run. The ones I've seen with cap issues had much worse damage and did it right as the power was applied in 1st of second. BTW, you should also pull the trans and check the sprague for damage.

Is a dana 60 with 456 gear out of a motor home worth 500 and would it work under a duster.

No. HD truck danas have full floating axle bearings and axles. So they need to have the axle ends cut off and std pass car flanges welded on, then new axles, and you still have no provision for pinion snubber for those that like them. The best way to get a pas car dana now if you are racing is brand new, made to order. Instead of buying a core, then repalcing everything (or most things).

rear held up today good

3 minutes into it
http://www.youtube.com/watch?v=b-c-iC4lYEs&feature=channel_page (http://www.youtube.com/watch?v=b-c-iC4lYEs&feature=channel_page)

http://www.youtube.com/watch?v=JdvaSvqo0qA&feature=channel (http://www.youtube.com/watch?v=JdvaSvqo0qA&feature=channel)
http://www.youtube.com/watch?v=0iQKCnaPsOU&feature=channel (http://www.youtube.com/watch?v=0iQKCnaPsOU&feature=channel)
http://www.youtube.com/watch?v=Q8euolyRGiM (http://www.youtube.com/watch?v=Q8euolyRGiM)

My 8.75 lasted about half a season at the track . It was a fresh rebuilt 742. Of course , it grenaded on the starting line in the semi-final round .....:angry7:

I went Dana 60 . No more worries. :read2:

.................Better check ur trans.................kim...............

trans is brand new, thats what I was also testing !

what about a ford 9 inch? it would be nice to keep the easy gear swap aspect of a center section rear.

if i could do my car over that is the only thing i would change. for what it cost to re-build a 8.75 rear, i could have bought a mail order 9 inch.

After fixing the center, an axle breaks...
http://bbdart.com/mycar/kcar/brokenaxle.wmv

Can't view it.

Can't view it.
Just a .wmv file. Maybe save and then open will work.

I guess the thing is to know when to upgrade. I think most guys (me, anyways) build stuff not realizing they may be making more power sooner than they think. Plus the cost factor...........

what about a ford 9 inch? it would be nice to keep the easy gear swap aspect of a center section rear.

if i could do my car over that is the only thing i would change. for what it cost to re-build a 8.75 rear, i could have bought a mail order 9 inch.

then you would be slower , the 9" uses MORe hp to turn by design , the GOOD 9" stuff is MORE expensive than the dana

then you would be slower , the 9" uses MORe hp to turn by design , the GOOD 9" stuff is MORE expensive than the dana

Yeah my car came with a decent 35 spline 9", but I would rather have a Dana, even with the ease of gear swaps.

Traction and horsepower will do that.

Folks, let's not forget that most of those SS/DA and SS/EA Hemi "E" bodies all came with and most ran the 8 3/4 rear. Also the SS/FA and SS/GA 440 cars! Those guys were in the high 9's and low 10's 20 years ago!
Back in the late 70's Jim Kinnett made a 12 bolt live in his SS/AA Barracuda for MANY passes. They can be made to live.

then you would be slower , the 9" uses MORe hp to turn by design , the GOOD 9" stuff is MORE expensive than the dana

The HP difference is so miimal it's almost not worth even mentioning or typing it. The weight diff is very small as well.

wagonmaster, your 100% right, This particular Dart is not a stripped down race version like the ones you mentioned. And such the debate on the rear is where this all comes from, OH, welcome aboard.

you had better have the trans checked out it might of screwed it up to i had the same thing happen and it broke my foot go to a web www.benchseatracin.com (http://www.benchseatracin.com) and check out the pic of a 727 exploded trans

Put a Dana 60 in it and be done. 8 3/4's can only handle so much torque and hp, and it looks like yours met it's limit.

wagonmaster, your 100% right, This particular Dart is not a stripped down race version .
Nope 3313 pounds !!