I have a secret to share: I’m not a fan of most visual car mods. Much of the time, I think manufacturers get it right from the factory. Stuff like huge fender flares, aftermarket spoilers, different headlights, and even wheels usually detracts from a car’s looks (in my opinion).
Once in a while, a tuner shop comes along and blasts my commonly held beliefs to bits. The VeilSide RX-7—the one made famous by The Fast and the Furious: Tokyo Drift—is the best example. While the original FD RX-7 is painfully pretty, I can’t help but be more excited by the VeilSide car. It feels so much more special to my eyes (maybe because Toyko Drift is the first Fast film I saw in theaters, but that’s another story).
My point is, I’m rarely ever excited by tuner cars. If I’m going to tune a car, I’d prefer to do it on my own terms, to fit my own needs. Usually, those changes are limited to brakes, tires, and maybe some suspension work. But this latest build from RTR, Vaughn Gitten Jr.’s Mustang-focused tuner company, is different.
The car is called the Spec 5, and it’s supposed to be RTR’s new halo car. Naturally, it’s based on the current S650-generation Mustang GT equipped from the factory with Recaro seats and the Performance package, which includes stuff like bigger Brembo brakes and a 3.73-ratio’d limited-slip rear differential.
The biggest change, and the one that gets me most excited, is the total widebody conversion. From the looks of it, the new flares aren’t just some tacked-on nonsense. RTR’s gone and redesigned every corner to accommodate a larger space for the wheel wells, using new composite panels that blend into the existing body seamlessly. The fender pieces are entirely new, while the rears mount to the existing metal.
The coolest bits aren’t the flares themselves, but how they’re integrated (or more accurately, not integrated) into their respective trailing edges. Instead of tracing back into the body, RTR cut them off and added carbon fiber panels, along with a set of brightly covered fins to break up the space underneath. Not only does this help alleviate pressure around the wheels, but it also just looks wicked.
There are other visual changes I like, too. RTR has managed to carve out a reputation for its intake-mounted LED lights in the nose, which is something I’d definitely have if I owned a Mustang. I’m also a fan of those 20-inch forged wheels, which are wrapped in Michelin Pilot Sport 4S tires. Stuff I’m less likely to want, but that’s still worth mentioning, is all the carbon fiber add-ons. That includes a splitter, rockers, and rear quarter extension pieces. In my experience, low-down carbon body pieces end up being more of a liability, especially if you drive the car properly.
No RTR Mustang is complete without a huge increase in power. The Spec 5 has that in droves thanks to a Whipple supercharger system, which pushes the 5.0-liter Coyote V8 to 870 horsepower and 660 pound-feet of torque. That’s even more than Ford’s own top-dog GTD. Unlike the GTD, you can option the Spec 5 with either a 10-speed automatic or a six-speed manual transmission. Shout out to Ford for keeping the three-pedal dream alive.
Keeping all that power in line is a host of under-the-skin upgrades. There are adjustable coilovers up front, with adjustable dampers and height-adjustable springs in the rear (the S650 has separated springs and dampers out back). There are also adjustable sway bars and heavier-duty two-piece front rotors for those Brembos. On paper, the Spec 5 sounds like it’d be a riot.
Of course, all tuner cars sound like they’d be a riot on paper. Driving them is usually a different story, since tuner firms don’t have millions of dollars to spend on months of ultra-fine-tuning and validation testing by engineers. But RTR has been around since 2009, and I’ve never heard of them putting out any real stinkers. So I’ll remain cautiously optimistic until I drive it.
Not that I’ll likely have the opportunity. RTR is making just 50 of these Spec 5s for the 2026 model year, each priced from $159,999, including the price of the Mustang GT donor car. That’s just about half as much as a GTD, by the way. That number can very easily balloon based on options. I’m most fond of the available custom color program. From the release:
Every Mustang RTR Spec 5 owner has the opportunity to personalize their vehicle with a standard color from the RTR Extended Color Palette, included in the base price, or elevate it with premium and paint-to-sample options for a truly bespoke finish.
As part of the experience, each owner receives a render of their Spec 5 showcasing their chosen exterior color alongside the three available wheel finishes. For paint-to-sample selections, RTR also provides a custom render and a physical speed shape painted in the selected color for final approval, making the customization process every bit as thrilling as the performance it delivers.
With this level of customization available, Spec 5 buyers have no excuse not to get an especially cool shade. We recommend using the GTD my boss David Tracy road-tripped to Monterey earlier this year as an inspiration.
Top photo: RTR
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Ugly. Even Mustang Mockery looks better with 8″ inches of ground clearance and 5 doors
That splitter looks like it would barely survive the drive off the lot. I’m not a fan of the fenders either. It all just looks like something someone who was really into the F&F franchise would do. Fine. You do you. Not something for me.