How much can the stock center diff take?

[kylush]

Ok heres the deal, my car is working on destroying its second transmission and I am going to get it rebuilt by sheptrans... that is if I keep the car but that is another story.

I am really debating between the Shep stage 2 and Shep stage 3 rebuilds. Sheptrans.com

As far as what I can see the only differences between the stage 2 and 3 is the stage 3 comes with a 4 spider center diff instead of the stock 2 spider, and it comes with a heavy duty 3-4 conversion and a new intermediate shaft.

My question is how much can the stock center diff take? I just want about 350hp outta my car and the stage 3 says its for 400-600hp street/strip cars so i'm wondering if I would be ok with the stage 2 rebuild. Like be able to take it out, rip on it, maybe take it to the track a few times, and daily drive it without worrying about it breaking. Or should I step up to the stage 3.

 

[donniekak]

At 350 your probably not going to be killing 3rd and 4th unless you use nlts. If you launch you car at all get a 4 spider, or welded diff. Most of the shops will install a 4 spider, or welded center diff in any of their builds. Try calling shep.

 

[kylush]

Ok sounds good... so i should probably go with the stage 3 then cause it has the 4 spider center diff... or see if he can add the 4 spider center diff to a stage 2... Maybe the stage 3 would be the better choice just becaue i could be pretty much sure it shouldn't break.

 

[blownturbotsi]

What do you have done to your car that makes you believe that you're making enough power to break trannies? Are you still using a 90 tranny/xfer case? Look around for a 91 combo and get it rebuilt and just add a welded center and a double cone second. You should have no problems at all. If you drag race often, a taller 1st will cut your 330's down a bit as well as put you in a good spot when you shift to second.

 

[kylush]

What have i done to make me believe it's capable of breaking trannies? Um... break two trannies? and yes i'm still running a 90 tranny and transfer case. I didn't know i could run a 91 combo and don't really wanna run a welded center diff because this car is my dd and i have heard lots about tire wear problems and other issues with them.

 

[blownturbotsi]

You'll have to get the 91 shifter and cables, but I have a 90 with a 91 combo and a welded center. It was and will again be driven quite often as soon as my turbo comes in.

There are some things that you have to give up like sharp turns and you'll have to make 17 point turns instead of 3, but it's cheaper than a spider.

As for the breaking of the trannies, I was leaning more towards how do you know it wasn't just bad trannies? How are you driving to where your under 300whp car is breaking them? Are you using a 4 puck or unsprung 6 that is shocking the shit out of it? I'm just trying to get to the bottom of your issue.

 

[kylush]

Nope, stock OEM original clutch. I beat on it a little and have launched it a couple times but what is the point of having a quick little awd car if you can't have fun with it?

 

[blownturbotsi]

Well, having fun and beating the shit out of it are two different things.

 

[byebyev8]

I'd say anything faster than 13's has a high chance of breaking the stock center diff, But some people run 11's on the stock diff with no problems at all.

 

[blownturbotsi]

I'd say anything faster than 13's has a high chance of breaking the stock center diff, But some people run 11's on the stock diff with no problems at all.

If this was the case, why would say, a Shep stage 4 come with a welded stocker...?

 

[byebyev8]

(stock center diff) as in not welded or without a spool. A spooled or welded diff is stronger than a 4spider.

 

[blownturbotsi]

(stock center diff) as in not welded or without a spool. A spooled or welded diff is stronger than a 4spider.

I understand what you said now.

 

[kylush]

Well, having fun and beating the shit out of it are two different things.

Lol I don't beat the shit outta it. I just daily drive it and get on it from time to time. I think i have maybe launched the car a total of about 4 or 5 times since I got it and I usually shift pretty gentle too. I don't drive it any harder really than I have driven any of my other cars but I have 10 times the problems. I don't get it tho its really frustrating me and making me wonder if it's even worth fixing or if I should get rid of it.