Installing A Sheetmetal 9-Inch Housing Rearend - Staunch Launch - Fox Buildup, Phase 3

Stop me if you've already heard this one: Some guy buys a Mustang. He adds a few bolt-on modifications. Then, before he knows it, he realizes that he's built a racecar and he's not sure how to feel about it.

Yeah, I know. That story is all too familiar to many of us in this hobby. On the outside looking in, it probably seems like we are building our LX into a racecar, but that is simply not the case. There is a distinction to be made here, and it involves the general philosophy guiding our project.

This is a street car we're working on and it will not be gutted out in the pursuit of low e.t.'s. However, we said from the beginning that our performance goals are lofty, so certain concessions must be made. As of this writing, we're putting the finishing touches on a new power plant for our '89 that should be capable of four-digit power. Accordingly, a complete overhaul is needed for the drivetrain in order to effectively deliver that power.

The major sticking point was the difference between street and race equipment. For a serious street/strip application, JC prefers the company's 35-spline S/T axles with a locker differential and an 8620 steel gear set. But when I told JC we were shooting for 1,000 hp at the tire on pump gas with the possibility of switching to C16 and going for really big numbers, he insisted that we step up to Strange's race-only equipment.

Of course, that would contradict what Editor Turner and I set out to accomplish from the beginning of this project. Street-ability has always been a key component of our build philosophy, so I was hesitant to go the race-only route. In the end, I posed this question to JC: If it was you sitting in the car getting ready to release the transbrake on the starting line, would you rather have the 35-spline street axles or the 40-spline race rear? He says the race setup is necessary at this power level, so we agreed, but with one caveat: We are hanging onto the LX's existing 31-spline 8.8-inch rear so it can be swapped in for extended street driving. It's a complicated proposition, but we won't compromise on safety.

With that said, JC cooked up a nice setup for our '89 LX. The boys at Strange Engineering started with their sheetmetal 9-inch housing, narrowed it 4 inches overall, installed suspension mounts in the factory locations, and reinforced it with a back brace. Next they loaded it with their 3.812-inch bore Ultra Case center section with a 40-spline spool; billet aluminum pinion support; large-stem, 9310-steel 3.50 pro-gear set; and chrome-moly yoke. The 40-spline gun-drilled Pro Race axles feature lightening holes in their flanges, along with 5/8-inch wheel studs. The finishing touch is a set of Pro Race brakes with billet-aluminum, four-piston calipers and vented steel rotors. A 9-inch rearend like this would be right at home in a 2,000hp Outlaw Drag Radial ride, so we shouldn't be anywhere near its physical limits. This provides the driver with much needed peace of mind!