8 3/4 VS Trans Brake

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VIZ

VIZ

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will a 8 3/4 live w a trans brake? 3500 lbs car The motor right now runs 11
:99 to a 11:20 with a 340. Next motor 421 stroker gears 4:30 or 4:88
 
Is it a stock 8 3/4 rearend? The weakest link is where the problems will happen. I replaced my 8 3/4 before i even made a single pass. Cuda is running a 9" with a spool and 4.56 gears.
 
I've used a brake with the 8.75 in my Duster. Weighed 2960 and ran mid tens. But I have the MP aluminum center section and a 4.86 Pro gear with a spool. It's in the Scamp now, it takes quite a beating. I just replaced the ring and pinion because I was getting a little worried about it after so many years but it looks fine. I think I'll have it magnafluxed just to be sure and keep it for a spare.
 
I always build my cars from the rear forward, if there is a weak link the track will bring it out. I would say if you built an 8.75 ok but why not just do a Dana or if you need to change gears build a 9 inch back braced. It's a whole lot cheaper to do it now than do it later after it breaks and tears a bunch of stuff up.
 
skypower said:
I always build my cars from the rear forward, if there is a weak link the track will bring it out. I would say if you built an 8.75 ok but why not just do a Dana or if you need to change gears build a 9 inch back braced. It's a whole lot cheaper to do it now than do it later after it breaks and tears a bunch of stuff up.
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back braces have a tendency to make the housings warp even more and then lock them in place even when jigged...

but as far as the rear if you are worried go to a dana... you can get everything (axle to axle) from strange for about 2K shipped...
 
With the current power? Maybe...

With more power?? Maybe...if it has a spool, a billet cap, fresh gears, housing brace...but at 3500 lbs, you're pushing it believe me.

One word here gives mucho piece-of-mind: DANA.
 
Thanks for the feedback. I am running richmond 4:88 w/ spool 742 case, moser 30 spline billet yoke but no billet caps. always tring to beat up my chevy friends w/ least as possible
 
I agree with some of the posts here. The 9" is a good choice but not a stock one. They are no stronger than a stock 8.75. To do a 9" correctly it requires expensine aftermarket parts. So much so that it's cheaper to do a complete Dana. To do the 8.75 is also pretty expensive and it's life expectancy at that weight is questionable. I know some have done it, others couldn't make it live. The other problem with the 8.75 is only one Pro gear is available and it's a 4.86 ratio.

I'm sticking with mine until I start breaking it on a regular basis, you might want to cut your losses now.
 
ray lewis local bro has one. toast.
1/4 mile 8.60 second stroker turbo small block
off the line @ budds creek this summer ..sheared all the studs on drivers side/ twisted the housing..lasted 4 years..now dana 60
 
Yeah u guys convinced me. Dana 60! I think I will use 8 3/4 to find the ratio I want then go pay $ for Dana. As far as the 9" i would not put it up against the 60 for toughness. And then there is the look. That big sucker from the back in an a body, bitchin ! Plus all mopar
 
VIZ said:
Yeah u guys convinced me. Dana 60! I think I will use 8 3/4 to find the ratio I want then go pay $ for Dana. As far as the 9" i would not put it up against the 60 for toughness. And then there is the look. That big sucker from the back in an a body, bitchin ! Plus all mopar
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Ray Lewis Blue Onmi last year when he ran 9.20's
[ame="http://www.youtube.com/watch?v=urb1xyV_TPg"]YouTube - ‪75-80 September 20,2009 U.S.A. Ray Lewis Carb'd‬‏[/ame]
 
Usually the 8-3/4 will start loosing ring teeth and theres nothing you can do about it. Some guys get lucky, others not so much. Its a crap shoot.
 
LXguy said:
Takes less horsepower to turn a 9" than a dana 60.
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It's the other way around. The 9" pinion contacts the ring gear too far below the centerline. Everyone thinks they're so strong because of the third pinion bearing. Truth is it has to have that bearing because the front pinion bearings are too close together to support the pinion gear shaft.
 
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