After 9sec9 killed a rear diff in his hot rod we started looking into options to cure the problem, and came up with a solution to lose half the weight of the diff and eliminate breakage. I would like to hear if anyone else has had those same issues at a similar power level or higher. Any shop is welcome to comment. Thanks, Indy

 

I don't have issues with rear diff breakage yet but half the weight you say? I assume this would reduce rotational mass?

 

I have seen a few cases of damage to rear diff. Some of the cars are producing a great amount of torque. Others seem to damage them bc of driver error. By driver error It can be either dumping the clutch, or they go past the staging lights and back up. When they back up they stop as soon as the light restages. This seems to make the rear wheels lock together and does not allow for the slip to happen.If they were to back up past the lights and roll foward, the rear seems to unlock and no damage occurs.

 

Yes aprox 50% reduction in weight to the diff. Yes it will reduce rotating mass . This is a drag race only mod.

 

As in not intended for DD street cars?

 

Our Orange car is still on the stock rear diff that the car came with and Brandon has not broken a rear diff either. Knock wood. Launch technique and having the car properly setup has alot to do with it.


Keith

 

Right, not for street use. I came up with the concept and 9sec9 and I had ten of them built by a friend who has designed diffs for F1 and Indy Cars. He has over 30 years of building components for a who's who of auto racing. I'm building up two for 9sec9 to run.

 

Indy, I just saw this thread and agree with some of the posts concerning reasons for failure. My concern is to avoid the loss of a $3000 rear diff. Accidents DO happen and since it's happened once, it can happen twice and that's what I wanted to avoid. The new pieces will be installed in both of our 'track' rearends, but the brand new street rear diff will be left alone. Since the parts are already being completed, as we speak, I would rather pay less than $1000 and beef them up, than take another chance on destroying a $3000 diff. My intention is to pull the carrier and put it on the shelf. Congratulations on your new relationship with Wilson by the way. I've been a little busy with some new software and another new data supplier, that I haven't had the chance to log in since Friday evening. This EvoM time has cut into my 'coding' time and that's why I'm at work on Sunday playing catch up. Jim, Thanks again for your help in getting the R&D completed for all of my pet projects. It will be good to see Wilson setup as a vendor on EvoM. Keep up the good work.

 

Sounds very interesting Jim. Love to hear and see more on this. I too rather spend 1k? to build it up then buy a new one at 3k when the stocker fails...

 

They are going to heat treat this week and should be ready to go Friday. For a race only Evo this should be hard to beat.

 

I broke a rearend... what do you suggest for me?

Congrats on your new job Wilson Manifolds

 

Help... lots of help. Thanks, Buddy

 

I am guessing you are making a spool. If so have fun with the center diffs and t-cases.

 

Care to explain? How it would know the difference between a spool and a diff in a straight line.

 

You are correct in a str8 line it will not know other then wheel spin.