KJ Jones Senior Technical Editor
January 4, 2007
Photos By: KJ Jones

Horse Sense: With all due respect to the new age of 'Stangbanging, part of our mission with our project '86 T-top coupe has been to keep Fox Mustangs in people's minds, and do our part to try to ensure there will never be any true, all-out end to one of the most popular platforms in Mustang history.

When all is said and done and our T-top-coupe project is complete, no one will be able to dispute the fact that the car and the project helped bring about some cool, new technology for '79-'93 Fox 'Stangs. This is significant because it has been more than 25 years since the popular Ponies were introduced.

We're technically now in an era that can be considered the twilight period/swan song for the Fox platform. Enthusiasts' interest in 'Stangs of this vintage is beginning to fade, thanks to the steady rise of S197 performance and the unofficial recognition of Two-Valve, '99-'04 cars as today's Mustang of choice.

Let's face it. The '86 T-top coupe we've been working on since February 2006 is a 20-year-old classic, albeit rare, Mustang. It has been great having companies embrace our idea of never forgetting the 'Stangs that started the movement, and investing their time and resources to create new products for Foxes at this stage in the game.

One of the new Fox concepts we've been stoked about is this FAB9 rearend and rear suspension from Chris Alston's Chassisworks, the noted chassis-component company that also developed the T-top-specific Mustang rollcage we featured in our July '06 issue ("'Cage Match," p. 176).

We first met Chris Alston Sr. at the '05 PRI show in Orlando, Florida, and spoke with him about our project. Chris explained that Chassisworks did not offer anything made specifically for Mustangs, but said he was interested in doing so and wanted to hear more.

After listening to our vision of bringing the rare 'Stang back to life in the form of a real-world, street/strip ride featuring new concepts in areas we considered necessary at this juncture or that would be accepted as cool by many of our readers, Chris wholeheartedly embraced the project. A short month after hauling the coupe to Chassisworks' massive headquarters in Sacramento, California, we were looking at the all-new, Fox-specific version of the company's fabled FAB9 rear, as well as upper/lower control arms, a coilover rear-shock system, and an adjustable antiroll bar, that we've been anxious to tell you about.

Now, before those 'Stang enthusiasts/ purists who have bashed this project from the outset mount a knee-jerk-reactionary letter or Internet-post campaign to complain about these suspension pieces being "one-off," or "custom," or even "unnecessary," we suggest they read this entire report.

As we've said in prior reports, one of the cooler aspects about the reconstruction of this ride is that we've been able to use parts-we like to use the term shelf parts- that are available for anyone to purchase at any time. We're trying to stay away from the over-the-top custom stuff that oftentimes goes far beyond the realm of doable for many readers' budgets.

With that said, yes, the parts developed by Chris Alston's Chassisworks are expensive; there's no disputing that. We also know that a stout 8.8 can be assembled for less money, and if done right, can have the same 1,000-plus-horsepower capability as our rear. But if you're really interested in bolting on the ultimate in hassle-free, direct-fit, bulletproof, 9-inch rears under your 'Stang, you'll definitely want to con-sider stepping up to a FAB9 housing and completing it with Strange axles, third member and gears, a Detroit Locker for street/strip or spool, and Wilwood rear brakes, as we did.

As mentioned earlier, our coupe's mild-steel FAB9 (chrome-moly is available as an option for the rear housing and upper/ lower control arms) is complemented by the new rear-suspension system that Chassisworks developed. The suspension parts are centered on adjustable Pro-Upper and Pro-Lower control arms and equally adjustable VariShock rear coilovers. The cool thing about the shock mounts is that they are positioned in the factory location and maintain their OEM shock angle, which many classes in the popular Mustang drag-racing sanctions require. One thing to note about both the upper/lower arms and the shocks is that Chassisworks has incorporated provisions for up and down adjustment into their mounting points on the FAB9, which expands the range for lowering a Mustang, or making adjustments that optimize launch characteristics (hooking and going straight) when you're at the dragstrip. A unique antiroll bar rounds out the Chassisworks suspension system. We also added Maximum Motorsports' full-length subframe connectors to tie the front to the back, as those parts are not available from Chassisworks.

After assembling the FAB9 in the driveway, we carried the rear and other suspension parts down to B&D Racing in Canoga Park, California, for installation. The parts can be bolted on at home in do-it-yourself fashion, but be aware the rearend is burdensome and might be a struggle to muscle into place. At B&D, everything went smoothly for Mason "Mase" Rowland, the shop's lead technician who handled the install for us. Once Mase got our coupe set up a twin-post lift, the entire installation came together in about five hours.

The photos say more about how trick this setup really is. We're using the street/strip setup with poly bushings, but a full-on race deal is also available.

Mason "Mase" Rowland of B&D Racing starts the goodbye process for the project car's stock 8.8. We're yanking this unit of unknown gearing and condition, and replacing it with the all-new, bolt-in FAB9 rear by Chris Alston's Chassisworks. Note the bracket mounted on the frame, to the right of Mase's hand. That's for one of the antiroll bar links. Both link brackets were permanently installed by the crew at Chassisworks, who used our car for the development of this new Mustang rearend and suspension system.

Here's a look at the complete FAB9 rearend housing, Strange Engineering's 35-spline Street/Strip (S/T) axles, nodular-iron S-Series case (loaded with 4.11 gears and a Detroit Locker differential), and all the rear-suspension components. The mild-steel FAB9 (PN 84M40-30 w/back brace and antiroll bar; $1,227) is shipped in raw metal form, so Johns Customz and Performance took care of colorizing ours while the car was being painted. Since the development of our FAB9 rearend in February 2006, Chris Alston's Chassisworks has added six additional bolt-in FAB9s for Fox through S197 Mustangs, available in mild steel or chrome-moly, and including poly or spherical bushings. Housings can be shortened between 11/44 and 3 inches (for mini-tub applications) at no additional charge. We suggest you call Chassisworks to speak with someone there who can help you select the rear that best suits your needs.