KJ Jones Senior Technical Editor
June 1, 2008
Photos By: KJ Jones
What's right with this picture? Well, if you're sharp enough to notice that the Pony-style wheel has a five-lug Ford bolt pattern, you're absolutely correct. But that's not all. Keep reading to see why this wheel and Mavromont Industries' other Pony Rs are special.

Horse Sense: "You're going to try and do what?! Put 17-inch 315 rear tires on a Fox?! Without mini-tubs?! Man, they're nearly 11 inches wide-there's no friggin' way. It's impossible!" That was the reaction of Race Pages' associate editor, and your tech editor's good friend, Jason Reiss after hearing about our intentions of mounting huge meats on the back of our project coupe. This one's for you, Jase, and all the other nonbelievers out there.

As hard-core enthusiasts, we all have a good understanding of how important aftermarket wheels and tires are to the ever-evolving process of modifying a '79-'08 Mustang.

Upgrading to larger-diameter/greater-width wheels and bigger tires is more the rule than the exception for many 'Stangbangers of the '99-to-present era. The envelope for how big a wheel-and-tire combination can go is being pushed all the time.

Fox owners, on the other hand, must live with a fixed limit: a 17x9-inch maximum wheel size. In addition, 255/45 17s and 275/50 17s are the tallest/widest front and rear tires that will fit comfortably inside the wheelwells without modifying them or narrowing the rear end.

Sure, the extra inch of the 17x9s is a nice step up from the 16-inch wheels and rubber worn by many cosmetically upgraded '79-and-up 'Stangs. However, it still misses the mark for those enthusiasts who want to put 17s on their street Foxes and capture a drag-race appearance in the process. Mustangs from 1991 to 1993 received 16-inch rolling stock from the factory, and '93 Cobras and Cobra Rs were fitted with 17x7.5-inch (four-lug) and 17x8-inch (five-lug) wheels, respectively.

This is the rear tire that Demetrios is talking about, Nitto's 315/35ZR-17 555R Extreme Drag Radial. The tire measures approximately a full inch wider than the 275/40ZR-17 that many consider to be the widest rear tire that will fit on a '79-'93 'Stang, without requiring chassis, body, or suspension mods that can go far beyond simply rolling the fender lips and banging on the inside wheelwells with a sledgehammer. Our project car will definitely look intimidating from the rear.

Thanks to the popularity of drag racing Mustangs in the NMRA and other sanctions, the wheel-and-tire-influenced "hot look" these days (especially for Foxes) is based on using 15x8- or 15x10-inch rear drag wheels and 15x3.5-inch front wheels. The widest, cleanest-fitting tires are used on the rear of the car and narrower tires (better known as "skinnies") up front.

Many of you have let us know how much you dig the Weld Racing 17-inch Alumastar 2.0 race wheels that adorn the '86 T-top coupe detailed in Editor Steve Turner's feature article in our Jan. '08 issue ("Top This," p. 102). Although the wheels are designed for S197 'Stangs, we discovered their 17x9.25-inch rear/17x4.5-inch front dimensions are Fox compliant. The way they look on our rare Pony is one of the 'Stang's greatest assets-along with 830 rwhp, of course.

Believe it or not, Weld's bad-dude race hoops weren't our first choice of wheels for the car. In the spirit of being true to Fox Mustangs and their history, your tech editor initially thought it would be beyond cool to have the T-top coupe roll on the ever-popular Pony star-style wheels-the 16x7-inch rolling stock that took the 'Stang world by storm when they were introduced on '91 LXs and GTs. A major setback was the fact that our coupe sports a five-lug setup, and a Pony-style wheel wasn't available with a 5-on-4.5-inch bolt pattern at the time we started mapping out the project car.

As we mentioned in our report on five-lug conversions for Foxes ("Four No More," Dec '07, p. 144), one of the biggest hurdles for enthusiasts who wish to make wheel upgrades on stock 'Stangs is the limited assortment of wheel styles that comply with the Fox's now-ancient 4x4.25-inch bolt pattern.

Well, it's a new (and better) time for Fox footwear. Thanks to a discovery made by our fearless leader, we're outfitting our coupe with a reincarnation of our favorite OEM wheels from Demetrios Mavrofrides and the crew at Mavromont Industries in Orlando, Florida.

With Mavromont's new Pony R wheels, our coupe has the throwback look that we wanted from the outset. These new-school Ponys (available in chrome and argent, the silver/gray color of the originals) are spitting-image replicas of the beloved '91-'93 'Stang wheels, save for unique center-cap emblems.

Our Pony R front wheels (PN 5055-086; $160 each) measure 17x6.5 inches and feature a 4.2-inch backspace (8.9mm offset). The wheels offer plenty of room for big-brake clearance. With their intermediate width versus a 3.5- or 9-inch wheel up front, they're great-looking, safe alternatives that help the combination look balanced when 285s or 315s are mounted in the rear.

The news of five-lug Ponys certainly is exciting for Fox purists like us, but these wheels have one specific quality that actually rates higher than their diameter and extra lugs. You see, the baddest version of this new wheel is 10 inches wide, and it features a 24mm offset. This makes installing Nitto's massive 315/35ZR-17 Extreme Drag Radial rear tires on Fox-body Mustangs possible-and it doesn't require mini-tubs, shorter axles, or anything beyond removing the useless quad shocks and opening up the inner fenderwells. More conventional 17x9-inch versions also are available for those who want a uniform look at all four points.

So now we're updating our coupe's appearance with Mavromont's version of a big 'n' littles combination for the street. Naturally, the 17x10s highlight this setup, but they're certainly not outdone in any way by the new 17x6.5 Pony R wheels that are going up front on our ride. While the new fronts aren't the slimline 3.5-inch-wide wheels that are more akin to this look, we feel they will offer a clean, balanced smaller-wheel appearance up front. With the addition of Fuzion's ZRI 215/50R-17 radials, they offer greater safety and stability when cruising down the freeway at a brisk pace. Associate Editor Johnson prefers traditional 3.5-inch-wide wheels up front, but he'll be hard-pressed to find a 17x3.5-inch Pony-style wheel anywhere.

Read on as we take you through our installation experience. Mavromont Industries' Pony Rs are definitely must-have wheels for any Fox owner and lover who wants their LX or GT to have the style of a super-stout drag 'Stang-with more rubber out back than it can stand without sacrificing any of the stocker-clean profile that forever endeared us to Pony wheels back in 1991.

"Our main objective is to offer wheel packages for just about every possible suspension or brake setup available for Fox-body Mustang owners," says Demetrios Mavrofrides of Mavromont Industries. "We were the first company to offer a five-lug 17x10-inch wheel (four-lug versions of the wheel also are available) specifically designed for Foxes [PN 5055-154/argent (silver); $133 each, 5055-156/chrome; $170 each]. Everybody else was selling 17x10.5-inch wheels designed for SN-95 Mustangs, which really don't leave enough clearance to fit 315/35ZR-17 rear tires on a Fox." Pony Rs have a 6.4-inch backspace for use with a standard-length Fox-body 8.8 rearend. The same wheel is available with a 7.3-inch backspace [PN 5055-174/argent (silver); $133 each, 5055-176/chrome; $170 each] for those who have SN-95 rears under their Foxes. Although backspace is the popular measurement enthusiasts reference when trying to determine correct wheel-and-tire sizes for their 'Stangs, Demetrios says wheel offset is actually the more important measurement, so much more important that it's accepted throughout the industry as the standard value used for determining fitment possibilities. Offset for our wheels is 23.8 mm. The figure is doubled (46 mm) for 'Stangs with post-'93 axles in the back.

Rudy Guardado, a technician at the Firestone Auto Care Center in Reseda, California, assisted us with mounting and high-speed balancing our coupe's new rolling stock. Tape-on weights are affixed to the back of each wheel to ensure there won't be any abnormal vibration or ill handling coming from the tires when we're rolling down the boulevard at a nice clip.

Once the tires are mounted and balanced, installing everything is an afternoon project that requires only a few tools. Critical tools include a 4-pound (long-head and handle) and 3-pound (short-head and handle) sledgehammer; a bright marking crayon; and Snap-on Tools' 18-volt, 1/2-inch-drive cordless impact gun (PN CT4850; $449.96).

The outer lips of our coupe's rear wheelwells were trimmed and rolled in a pit-side thrash at PINKS All-Out: Las Vegas ("Lights, Cameras...Action!" Mar. '08, p. 128), but having Eastwood's fender roller (PN 31158; $249.99) handy is a good idea, as the outer areas may require some attention if your 'Stang is lowered. We also had a cutoff wheel and a pair of snips on standby, but the job didn't require using either of those tools.

For a non-mini-tubbed Fox 'Stang, 6.5 inches of backspace offers the best fitment of 10-inch-wide rear wheels. Mavromont's Pony Rs' backspace checks in just below that maximum. We verified this by laying a wheel face down, then placed a straightedge diagonally across the inboard flange of the wheel. Using a tape measure, we measured the distance from the intersection of the straightedge and the wheel's inboard flange to the wheel's hub-mounting pad. That distance equals the amount of backspace.

For street purposes, the coupe was equipped with 17x9-inch replicas of '07 Shelby GT 500 wheels, with 275/40R-17 Nittos in the back and 235/45ZR-17 555s in the front.

The project car's AlumaStealth fuel tank doesn't leave adequate clearance for a standard floor jack, which can make things challenging when both rear wheels must be elevated. OTC's lightweight aluminum, 2-ton racing jack (PN 1532; $324.95) features a low-profile design that makes lifting our coupe's back end much easier. The OTC adjustable jackstands are there for additional safety, of course.

For grins, we measured the replica Shelby wheel's backspace and calculated 6.25 inches.

We mounted a new wheel on the 'Stang to determine the clearance-or lack thereof-of the wider 315 with the inner wheelwell. This is a look at the conflict area-the lip/edge portion of the wheelhousing's rear area. Our 'Stang obviously has rear coilover shocks, but on a stock Fox-body, it's the section just after the shock where the curve to the back of the inner wheelwell begins. The clearance concern is the same on both sides, and it will require a good amount of massaging to achieve an acceptable amount of space for the new tires.

Marking the area to be modified makes things much easier. Use a marking crayon or other bright-colored marking pen. The material below the mark is the stuff that must be eliminated.

Start by using the long-handled, long-head 4-pound sledge. The hanging metal that makes a sharp edge along the inside wheel must be knocked back toward the center of the trunk.

Then, using the top of the same hammer, bump the folded edge upward.

The smaller, 3-pound sledgehammer is then used to tap the folded material against the back side of the wheelwell. This is somewhat of a finesse procedure to make sure the original flow of the wheelwell is retained.

You can almost think of the process as reverse fender rolling. The backside of the inner wheelwell looks similar to an outer lip that has seen the business end of an Eastwood tool.

Although it isn't required, we gave the front portion of the inner wheelwells the same treatment as the rear. This was really just a peace-of-mind move since the front area isn't affected by the width of the 315s.

The modification process isn't all about making a few "love taps" on the rear wheelwells.

We suggest using a piece of 2x4-inch wood to really get the inner edge to conform.

We like to make sure the tires don't come in contact with any metal under the car, so we spent a great deal of time shaping the area and creating more than enough clearance on the front and back sides.

For comparison's sake, here's a look at the back of our coupe with a 315/35ZR-17 mounted on the 17x10-inch wheel (left) and a 17x9-inch-mounted 275/40ZR-17 (right).

...and here's the aggressive look that our project car now has with its big rear wheels and tires planted firmly on the ground.

One thing we really dig is the fact that 3-inch wheel studs have plenty of room for a clean fit underneath the Pony R's slick center caps.

Sure, our T-top coupe is without many things common to most street 'Stangs-namely a full exhaust system; standard rear shocks and coil springs; and in some instances, the original quad-shock system-but achieving this look is still possible for these cars, as the main modification is only the adjustment of the inner fenderwells. Removing the quad shocks is mandatory, and you may have to check for proper e-brake cable and tailpipe clearance, which can be achieved by rotating these pieces or moving them out of the way.

As Editor Steve Turner would say, Mavromont's big 'n' littles 17-inch Pony R setup is "the hotness" on a Fox-body 'Stang. We finished up just as the SoCal winter rain returned, which prevented us from adjusting the rear coilovers to bring the back of the coupe down a bit for a level ride height. The front springs don't require any adjustment. You can bet we'll make the suspension tweak as soon as it's dry again, and we'll be out on the road, cruising and turning heads with the project car's sinister new look.