The main upgrade is within...
The main upgrade is within the differential housing itself where we're stuffing a Zexel Torsen T-2R differential and Precision Gear 3.73s in place of the stock parts (shown above with the Precision Gear installation kit). Supporting items we'll be using include Moser 31-spline alloy axles and a Ford Racing Performance Parts driveshaft.
Horse Sense: The Zexel Torsen T-2R gear-drive differential is the heart of our 3g GT's rear axle upgrades. The T-2R unit, while offering full-time limited-slip capability, also offers constant torque-bias sensing and stability via an all-gear-driven differential. The T-2R does not use any friction material, clutch plates, or clutch cones to accomplish this, but instead it uses parallel-axis gears-a worm gear, if you will-that perform differential and torque-splitting functions. No friction material means there are no clutches to wear out, and no friction modifier is required in the gear oil.
For those just tuning in, our '01 3g GT Mustang project is all about forces- g-forces to be exact. Our mission is to achieve 1g of cornering, 1g of braking, and 1g of acceleration using bolt-on parts. So far, we've updated our screaming Zinc Yellow banana with an ATI ProCharger P-1SC supercharger, a Steeda suspension (including the company's five-link rear setup), Steeda 13-inch front brakes, and a Cervini's Cobra R body kit (hey, it has to look the part too). We've also spruced up the inside with Ford Racing Performance Parts leather seats, NR Auto Accessories electroluminescent gauges, MGW billet hardware, and a Year One brushed-aluminum dash kit.
Thus far, the performance parts we've installed have given the 3g GT a whole new feeling, turning a decent stock Mustang GT into a performance machine anyone would love to have. But we're just getting started. Later in 2003 (it's only September 2002 as this is written), we'll begin a Phase Two scenario with our project Mustang. Look for even bigger brakes, more engine enhancements, more handling improvements, custom paint with graphics, and much more. With the addition of Phase Two, the 3g GT will undoubtedly be able to post the g-force numbers we're seeking.
It's much easier to understand...
It's much easier to understand how the Zexel Torsen differential works if we simply show you an exploded view of the differential instead of trying to describe its internal operations. Suffice it to say, the differential works instantly and offers great traction and cornering abilities for a street or handling car. Just don't punish the Torsen with big slicks and extreme drag-race use.
Up to this point, the rearend-one of the most important areas of the drivetrain-hadn't been upgraded to handle the current power of this Mustang, let alone what we plan to throw at it in the future. While the 3g was busy being hustled from show to show during 2002, we had just enough time to get its rearend built up by LaMotta Performance, with the proper goodies from Reider Racing, before heading to the NMRA World Finals in Bowling Green, Kentucky.
After discussing the project with Tom Reider, we agreed that a Zexel Torsen T-2R differential with Precision Gear 3.73 gears wrapped around it would be the best answer for cornering and straight-line acceleration. To complete the upgrades, Tom suggested Moser Engineering custom alloy axles since the Torsen is a 31-spline case. We also contacted Kenny Holcomb at Holcomb Motorsports for an FRPP aluminum driveshaft because if you've ever driven a Mustang with one of these bad boys under it, you know every Mustang should have one. Finally, we cracked open a fresh case of Red Line synthetic gear oil to lubricate the 3g's new parts.
The installation wasn't complicated, but there were a few extra steps due to the Steeda five-link suspension mounting points. As we've said before, we don't expect you to perform your own gear swaps, but we want to show the progress our project car is making. Come out and see the 3g at driving, racing, and show events in 2003.
 LaMotta Performance technician...  LaMotta Performance technician Jay Meagher drew the short straw and was the lucky winner to work on our 3g Mustang (special thanks to Jake LaMotta for fitting us in so quickly before the NMRA World Finals). To access the differential cover, Jay removes the right Panhard bar mounting assembly from the axle housing since one of its support legs ties into the differential-cover mounting-bolt area. |  With the Steeda five-link...  With the Steeda five-link Panhard bar and mounting bracket out of the way, Jay removes the rest of the differential cover bolts and drains the barely used synthetic fluid from the differential housing. He then completely removes the cover. |  For the differential to be...  For the differential to be removed, the rear axles must be disengaged from the differential side gears. Jay removes the brake calipers and mounting brackets (wiring them to the frame so as to not hang from the brake hose). He then removes the delicate ABS wheel speed sensor so the sensor isn't damaged during axle removal. |
 With only the bare axles left,...  With only the bare axles left, Jay removes the differential cross-shaft retaining bolt and then slides the cross-shaft out of the differential. This allows the axles to be pushed inward so the C-clip retainers can be removed from the ends of the axle, allowing complete axle removal. |  Use caution not to drag the...  Use caution not to drag the axle on the axle-bearing seal (located at the extreme outer edge of the differential housing) or you will damage the seal and cause a gear-oil leak all over the brakes and rear wheels. Not good. |  With the axles removed, the...  With the axles removed, the differential can be extricated from the housing. Jay removes the two differential main-bearing caps (noting their sides and the directional arrows on them) and then carefully pries the differential out of the housing. |