[623]

Just a quick report on how good the M240i (mostly stock) is for track day use...

Track: Buttonwillow 13CW (California)
Number of laps: 90, mostly hot laps
Lap times: between 2.01.xx and 2.02.xx
Engine: stock
Engine oil: Rennline 0w20
Camber plates: Vorshlag
Brake pads: Hawk 60/30
Brake fluid: Motul RF600
Tires: Bridgestone R71Rs, square 255/40-18
Wheels: Apex VS-5RS 18"

Even though it was the first time driving this car on track, I drove with all electronic aids off (traction control and DSC). No problem at all. The rear went loose a few times, easy catch, the x-Drive system being probably helpful here.

The car is fast, the suspension in Sport+ is firm enough with no boucing or diving while braking. The "loud" exhaust in this mode is way too quiet for the track, you hear mostly the other drivers.

The engine didn't miss a bit, the engine oil temperature was the same than when cruising on the highway. I was really impressed as I was pushing hard. Shifting with the paddle was a no brainer, crisp and fast up & down.

The tires—while doing a good job overall—did overheat even with pressure kept around 32psi hot. Thanks to the camber plates, the shoulders are fine on all tires. However, the center threads took a hit, especially in the front. You can also see on the pictures that the tire texture show some clear signs of distress LOL. Maybe this tire degradation is normal on this tire, maybe it's a proof of pushing too hard, maybe it's temp related? Anone who knows is welcome to offer advice. I was expected more endurance from this set tbh.

Conclusion: the car was fast and reliable. Went back home cruising in silence on the highway, 30 mpg and no rattles. Can't dream of a better dual use car!

Long story short: If you wonder about tracking your M240i X-Drive, just do it!

[Littlecoupe]

Did you opt for the additional cooler package (ZTK)? I assume no since I don't see the fender arches? Good to know that cooling was not an issue if you are on the non-ZTK setup.

Also happy to hear no rattles LOL. I just spent a bunch of time and effort to get rid of a bunch of rattles in mine, but I want to track it a little this summer, but rattles are always a concern with that type of use.

[M2M3M3]

Nice! Great to see these cars properly used!

That hot pressure was awful low for street tires. Running 38psi would have helped the issue. Street tires don't like low pressures like track tires do.

[623]

Littlecoupe No cooling package for me.
tbh I don't really like the idea of the additional oil cooler being so close to the ground.
The engine oil temp never went above 232F, which is basically what I gewt during normal driving. It was 226F by the time I was half-way in my cool down lap...

[623]

Originally Posted by M2M3M3

That hot pressure was awful low for street tires. Running 38psi would have helped the issue. Street tires don't like low pressures like track tires do.

Funny, I kept removing air through the day to keep them at 32psi... I don't know where I found the info but I had this 32psi limit in my head as the recommended pressure for track use. I probably assumed that the R71Rs was some sort of a track tire disguised as a DOT tire?

[Ricochet48]

Wow so stock aside from tires, pads, and brake fluid... without the ZTK pack and you were find after 90 laps!

Honestly makes me question if the $2,400 ZTK package is worth it haha (still like the bigger brakes and nicer wheels, but hate you have to buy an aftermarket oil cooler shield).

[623]

Originally Posted by Ricochet48

Wow so stock aside from tires, pads, and brake fluid... without the ZTK pack and you were find after 90 laps!

The external temperature was pretty low though, barely reached 70F, so it might have helped?

Originally Posted by Ricochet48

Honestly makes me question if the $2,400 ZTK package is worth it haha (still like the bigger brakes and nicer wheels, but hate you have to buy an aftermarket oil cooler shield).

The brakes are not really bigger, the rotors are. So it's more weight, while my stopping power was way enough. I agree with you, $2,4k is a lot for something you might no need and adds extra weight and reliability concern...

[623]

Originally Posted by M2M3M3

Nice! Great to see these cars properly used!

That hot pressure was awful low for street tires. Running 38psi would have helped the issue. Street tires don't like low pressures like track tires do.

I noted the temps for all tires (inside/center/outside) after every single session and it went up indeed through the day, from basically 130F to 160F. It goes up logically when the track temps raise, but you might be onto something here. It looks like removing air to keep the tires at 32psi hot didn't make them so happy...

[M2M3M3]

Originally Posted by 623

I noted the temps for all tires (inside/center/outside) after every single session and it went up indeed through the day, from basically 130F to 160F. It goes up logically when the track temps raise, but you might be onto something here. It looks like removing air to keep the tires at 32psi hot didn't make them so happy...

Low pressures increase tread squirm, which adds heat. Street tires also don't have the sidewall stiffness track tires do. They need more pressure to be stable. Flex = heat.