Rear end

RileyDymond

Member
Feb 8, 2024
8
2
13
Ny
I’m doing a 363 dart block supercharged swap into my ‘89 fox. I have the majority of the chassis figured out for the power, but I’m stuck on the rear end decision just looking for ideas. I currently have the stock rear end with 3.73’s, 28 splines, 4lug rear disc kit, and lowering springs. What should I do to make it handle the power it’s going to have. No intention of dragging the car just a street car. Don’t know what’s really out there and what works/ needs to be done.

Thanks in advance!
 
I’m doing a 363 dart block supercharged swap into my ‘89 fox. I have the majority of the chassis figured out for the power, but I’m stuck on the rear end decision just looking for ideas. I currently have the stock rear end with 3.73’s, 28 splines, 4lug rear disc kit, and lowering springs. What should I do to make it handle the power it’s going to have. No intention of dragging the car just a street car. Don’t know what’s really out there and what works/ needs to be done.

Thanks in advance!
Also I’m into the sve series 3 wheels for the sn95. How would I get those to work besides 5lug conversion? Not sure if the size would rub on the quad shock, exhaust or fender.
 
Ditch the quad shocks and get a team Z motorsports Street beast rear set up( control arms, upper relocation ) also weld in some torque box re enforcement plates. A!so do the rear five lug disc ,and while your at it get a 31 spline carrier and axles.
Now I hope your trans is up to par.
 
This
Ditch the quad shocks and get a team Z motorsports Street beast rear set up( control arms, upper relocation ) also weld in some torque box re enforcement plates. A!so do the rear five lug disc ,and while your at it get a 31 spline carrier and axles.
Now I hope your trans is up to par.
thank you ill look into it trans is a t56 mag
 
The 8.8 tubes need to be welded to the center section.
The axle ends need to be converted to 9" large bearing "Torino" ends.
The axle tubes need to be braced.
You need to switch to 35 spline axles.
Billet carrier caps need to be used.
I use the Baseline Suspensions kit.
This combo has withstood over 1,200 hp for several years.
 
  • Like
Reactions: General karthief
The 8.8 tubes need to be welded to the center section.
The axle ends need to be converted to 9" large bearing "Torino" ends.
The axle tubes need to be braced.
You need to switch to 35 spline axles.
Billet carrier caps need to be used.
I use the Baseline Suspensions kit.
This combo has withstood over 1,200 hp for several years.
Definitely another option thank you

Also what’s your opinion about mosers m88 8.8 kit for my set up.

https://www.moserengineering.com/MOSER-TRUE-FOX-BODY-M88-88-Built-to-Order-Rear-End-Package.item
 
Definitely another option thank you

Also what’s your opinion about mosers m88 8.8 kit for my set up.

https://www.moserengineering.com/MOSER-TRUE-FOX-BODY-M88-88-Built-to-Order-Rear-End-Package.item
That's a nice kit.
Wish it was available when I built my 8.8

Oh yeah, get a billet yoke.
And one of these:
 
The shim style pinion spacer is an absolute must. Ratech also makes a nice pinion spacer. Have them in both cars and installer liked them vs the crush style which suck. Had to replace the pinion seal on the Coupe a couple years ago and it was super easy having this type of spacer in that it was remove the flange, pop the seal off, install the new seal, reinstall the flange and torque to spec. No worries on f'n up the crush sleeve or not torquing it enough.

 
  • Like
Reactions: General karthief
The shim style pinion spacer is an absolute must. Ratech also makes a nice pinion spacer. Have them in both cars and installer liked them vs the crush style which suck. Had to replace the pinion seal on the Coupe a couple years ago and it was super easy having this type of spacer in that it was remove the flange, pop the seal off, install the new seal, reinstall the flange and torque to spec. No worries on f'n up the crush sleeve or not torquing it enough.

I bought the Ratech one for this rear
 
How much money do you have to spend? I did the Moser 9" housing ends with the 8.8" bolt pattern (so you can bolt factory SN brakes right up), 33 spline axles, welded the tubes to the pumpkin, 2 braces, and most importantly and Eaton Truetrac differential. The Truetrac completely transforms the car. It has been hands down the best mod I have ever done. The primary reason for cutting the ends off and replacing them is to get the axle completely straight. The factory tolerances are like 1/4" which is why so many of these cars are so squirly on the road.

On a side note, I have another write up coming to StangNet soon. I am on track to have the only Mustang (in the World as far as I can find) with full size 9" bearing on the axles, a parking brake, full ABS functionality, and 4 piston calipers. I have a couple more details to work out, but no special machining work or custom parts, Just off the shelf stuff with some smarts.

Kurt
 
I’m doing a 363 dart block supercharged swap into my ‘89 fox. I have the majority of the chassis figured out for the power, but I’m stuck on the rear end decision just looking for ideas. I currently have the stock rear end with 3.73’s, 28 splines, 4lug rear disc kit, and lowering springs. What should I do to make it handle the power it’s going to have. No intention of dragging the car just a street car. Don’t know what’s really out there and what works/ needs to be done.

Thanks in advance!
I’m pretty sure stock rear gears aren’t 3.73. On my 86 it was 2.73 and I changed them to 3.55. Check what you have by jacking the car up and spin a wheel by hand and see how many times your driveshaft turns.
If you want a road car that will still have decent MPG, use 3.55.
 
I’m pretty sure stock rear gears aren’t 3.73. On my 86 it was 2.73 and I changed them to 3.55. Check what you have by jacking the car up and spin a wheel by hand and see how many times your driveshaft turns.
If you want a road car that will still have decent MPG, use 3.55.

Most autos came with 2.73s, and most manuals came with 3.08s. That being said, the dealer could order the car with whatever gear option they wanted. In the same way there were Yenko Camaros, certain Ford dealers were ordering cars with 3.73s, and even 4.10s.

Kurt