Some rear end questions

BlackArtemis

Dated 4 Amandas. Nothing special. Got the job done
Founding Member
Sep 23, 2002
0
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49
West Chester, PA
Ok, so it seems my LSD is going out.

Now I planned on doing gears anyways so it's nothing horrible.

The question comes down to, how far should I go?

I was planning 3.73's and eventually an S-trim.

Would the 28 splin Diff with carbon pack upgrade and 28 spline axles hold at 375-400 hp/tq?

Occasional drag day, but mostly a crusing fun car.

Or should I just go all out and put in a FRPP 31 spline Diff and moiser 31 spline axles as well.

If I just do the rebuild I could afford a clutch install as well.

(I will not install anything drivetrain related myself, I don't have the tools or know-how, so I gotta do it the expensive route :( )


The clutch is a prereq for my headers btw :/
 
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I was planning 3.73's and eventually an S-trim.

Good combo. 4.10s would also work well with a centri.

Would the 28 splin Diff with carbon pack upgrade and 28 spline axles hold at 375-400 hp/tq?

Generally, yes.

However, if you bolt slicks to it and pop the clutch at 4000RPM on a prepped track on a good day, YMMV.

Or should I just go all out and put in a FRPP 31 spline Diff and moiser 31 spline axles as well.

Depends on your budget. Building a stronger rear axle, especially if you plan a blower motor and occasional drag racing, makes sense and gives you a fatter safety margin. If money is tight the 28 can live but it has a lower tolerance for shock loads attendant high RPM clutch drops in high-traction conditions. If you stay 28, keep that in mind as you air down your slicks on race day :)
 
I guess the question is how much extra is it to go 31 spline with a whole new diff? But if you are going to pay the labor to get it done in the first place I would go ahead and get it done right the first time. Better to have more than you need than to be on the edge of what it can handle.

I have 4.10s in my t-trim equipped 01 GT, but its an auto.
 
I guess the question is how much extra is it to go 31 spline with a whole new diff? But if you are going to pay the labor to get it done in the first place I would go ahead and get it done right the first time. Better to have more than you need than to be on the edge of what it can handle.

I have 4.10s in my t-trim equipped 01 GT, but its an auto.

I agree with "04darkshadow" Its good insurance and just a few bucks in difference.
Even though i still have the 28 spline unit in my 99GT w/eaton posi and Richmond 4;10 gears since 01, ive never snapped an axle ran DRs for years and switched to MT/ET streets for the last 2 years w/100 shot. (i was fortunate) I Dont Drag race the car any more cause its my wifes D.D. in the summer and have another toy.
 
The repair vs the replacement question was brought up because I would be able to get the clutch done at the same time. But I have been leaning towards the entire rebuild. After reading a thread called "superchargers for $1500" I have decided that I will go the blower route. (The thread is great, but it will really cost you about $2000 + tune).

Anyways, so I was looking at all of these parts for what I need done. Anything I am missing?

Ford Mustang 3.73 Gears at AmericanMuscle.com - Free Shipping!
(gear size is not 100% decided on, but I don't feel like making the 999999999999999999999th thread about them, so I will be reading others)

http://www.americanmuscle.com/moser...ed Slip Differential w/ Carbon Discs^3^774.97

http://www.americanmuscle.com/ford-...ed Slip Differential w/ Carbon Discs^3^774.97

As stated before. I don't have a ton of tools and I have limited know ho. When it comes to something like drive train I am not going to attempt to save some $ and do it myself. So sadly it's going to cost quite a bit to install and I will have to put off the clutch install for awhile which shoves back the header install (Something I WILL be doing with some friends).

thanks for all the input