Why an F8X BMW? This chassis–sold as the 2014-2019 BMW M3 and 2014-2020 BMW M4 in the U.S.–is the ultimate platform for going fast, says BimmerWorld’s Phil Wurz. Autocross? No problem? Tracking? No problem. Drag racing? Yes, it can even do that, too.

F8X vs. E46 vs. E9X vs. F3X

Why this particular generation of BMW? Let’s start with the E46. Those cars are roughly 20 years old. “With the E46 parts, we’re seeing a lot of stuff go NLA,” says Phil. “The parts supply is golden on F-chassis cars.”

One generation newer, and you get the E9X and with it a V8. Certainly nice, indeed, but it’s not faster than the F8X, says Phil.

“BMW has been upping the performance with every new generation,” Phil says. “Yes, they get a little bit heavier, but, everything else, that F8X car does better.”

And then there’s the contemporary cousin to the F8X, the F3X. We felt that the F3X held so much potential that we have a 2015 BMW 435i as a project car. The F8X, though, offers more power, a more responsive DCT, a limited slip with a stepper motor, bigger brakes and wider fenders flares for bigger tires.

“This all comes with a price tag difference,” Phil reminds us. “Expect to pay probably double for an F8X, but depending on the example it could end up being more. The F3X is an amazing car, still.”

What to Look for When Buying One

The F8X came in several trim levels: standard, Competition, CS and the GTS.

“If you’re person who wants to take it to the track and not modify it, maybe a CS or GTS is your option,” says Phil. “They’ll be a little more money up front, but they’ll be a little more capable. However, if you’re a person who’s going to put a tune on a car, install a better suspension, fit wider wheels and tires–you know, go the GTMore route–all that stuff from the CS and GTS isn’t going to matter.”

Sedan (M3) or coupe (M4)?


Photograph Courtesy BMW

“That could come down to personal preference,” Phil says. “But a coupe is going to be about 50 pounds lighter than a sedan.”

Six-speed manual or a seven-speed DCT?

“If lap time is what you’re after, then the DCT is what you want to do,” says Phil. “I was once a stickler for a manual. But, when I first drove a car with a DCT, I was like, ‘Oh, I can’t shift that fast.’”

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Photograph Courtesy BMW

Carbon ceramic brakes or iron ones?

“The lighter weight of ceramic brakes can be a benefit,” Phil says. “But you’re locked into a 19-inch wheel with that system. If you have to do a replacement for that rotor, it’s like $3000 a corner. Having an iron disc is my preference and we have cost-effective iron conversion kits, but you’re still locked into 19-inch wheels, which get you into more expensive tires and more cost down the line.”

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Photograph Courtesy BMW

As far as finding a good example, be sure to look for signs of these cars being abused on track, as some were. Being a special car, though, many were treated as weekend rides and garaged otherwise. Phil says, as long as they’ve been treated well, the F8X is fairly reliable. However, it isn’t immune from issues.

“They have their typical BMW oil leaks,” says Phil. “Those are valve cover gasket, oil pan and oil filter housing. The other issue that’s common with these things is the crank hub issue. At higher power levels–typically cars that have been tuned–the crank hub can slip and mess with timing. Normally, the ECU catches it before any piston-to-valve contact by going into limp mode. But it is possible to have a catastrophic issue.

“There is a solution for that,” Phil continues. “We put in a four-pin-end crank hub that is more secure in keeping the engine in time. The factory system just uses friction washers and torque on the front crank hub bolt, and that’s the only thing holding it together. If someone has upgraded the crank hub, it’s probably a good sign they’ve taken good care of the car, because it’s not the cheapest thing to get done.”

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Photography Credit: J.A. Ackley

And yes, the F8X also has issues with plastic components, like other BMWs.

“Charge pipes fail at times because of increased boost or because of so much heat, and heat is hard on plastic,” Phil says. “Some people put aluminum charge pipes in to solve that.”

Let’s Go Motorsport It

It doesn’t take much to get an F8X out on track or at an autocross. “Throw some brake pads on it, hit all the fluids and go have some fun,” Phil advises.

It doesn’t take much to improve an F8X, either. Phil recommends replacing those charge pipes with aluminum ones, for reliability purposes, and then installing camber plates.

“There is no camber adjustability on the front from the factory,” says Phil. “That’s a good low-hanging fruit for more performance.”

After that, the path is clear as to what is next for Phil.

“Suspension is my first go-to, as it’s the foundation,” says Phil. “I leave power to later. Something that surprises people is how much suspension affects the braking. It benefits brake performance by not throwing all the weight around the car.”

What kind of suspension depends on what you intend to make your F8X do.

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Photograph Courtesy BimmerWorld

“If you’re going to dual-purpose it, something like a one-way non-remote setup that can handle decently high spring rates to support the car would be a great package,” Phil says. “If you’re going to do heavy track use, you can do something like the GTMore suspension package, which not only gives you the platform for better suspension handling but also has some tweaks with it that allows you to fit wider wheels and tires. It does have some compromises. You reduce your turning radius by a little bit. But James Clay drove that setup during One Lap of America and he was impressed with how well it handled the road. The GTMore with a high-rate spring and proper damper package rode smoother than a newer truck.”

Next, square that wheel-and-tire setup.

“Square is going to get the balance of the car so you get more front-end grip,” says Phil. “A smaller tire up front will make it understeer and, with a BMW, we’re always looking for more front-end grip.”

The good news, you can go wider easily with the F8X.

“The standard suspension can fit a 295 tire up front,” Phil says. “If you want to go the next level, such as our GTMore-like package, then 315s fit easily.”

Now’s the point you should go for upgraded brakes. It won’t only help you stop better, though.

“Our Alcon six-piston package is lighter,” says Phil. “We can also shed some weight with wheels and tires.”

Finally, now you can consider power. Remember, the F8X comes with 420 to 480 horses from the factory as is.

“They don’t need more power, but who doesn’t want more?” Phil says. “It’s super easy to turn it up. There are plenty of software options that add 100-plus horsepower easy, even on the stock turbos.”

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Photography Credit: Chris Tropea

However, with more horsepower comes drawbacks.

“When you increase horsepower, you’re going to increase heat,” says Phil. “You may need to upgrade cooling if you’re doing 20- to 30-minute runs. If you’re doing autocross, you’ll probably be okay. We had to throw the whole PWR suite at GTMore. We also did bigger turbos. We’re making 750 to 800 wheel horsepower in that car.”

Overall, the BMW F8X is a great platform to go out and do motorsport things.

“It will be a compliant, fun street car, and an awesome track car,” Phil says. “It’s capable out of the gates and it only gets even more capable.”



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