Our 2015 BMW M4 Track Build
For the past few years, I've been satisfying my need for speed by driving factory cars from Mercedes-AMG. I must say, as much as it was reassuring to know that all their cars were meticulously maintained by factory trained technicians and on top of that, I personally thought their on track support was second to none, I felt there was something impersonal about tracking a car that didn't belong to me. So around the end of November 2018, I decided that i wanted to track convert a car that we owned.
I was never a fan of the BMW brand and if anything I am still not a fan of BMW but for the sake of staying competitive and comparing their entry level super car to those from other German manufacturers, I found that the M4 gave me the most bang for my buck.
My first modification to the M4 was to the rims and tires. The car stock was running a staggered setup with- 18x8.5 in the front and 19x9 in the rear To increase front end grip which would give me an advantage when cornering, I decided to switch over to a square setup. I went with APEX EC-7 18x10" all around with Michelin Pilot 4s 275/35-18 tires. I also fitted 5MM spacers to make room for my coilovers.
Next on the list was coilovers, camber plates and brake pads. I went with the KW V3s with M-Suspension cancellation paired them with Ground Control camber plates and PAGID RSL29 brake pads. The install of the coilovers was extremely easy- luckily we had access to a lift and all the necessary tools. We really only ran into issues when we were installing the M-suspension cancellation kit. The instructions were not clear at all. I honestly think we spent more time trying to figure out how to install the kit than the actual coilovers. We then installed the Ground Control camber plates and for now, we set the front camber to -1 just to get the front tires to sit flush inside the wheel well. Regarding the PAGIDs, the initial bite when braking is a bit rough so modulating will take some time to get use to. My only real gripe with the pads is that they are extremely loud when cold.
Aesthetically, I removed the cheap plastic lip the previous owner installed and replaced is with carbon fiber.
Same with the rear diffuser. I'm not sure what BMW was thinking when they decided to fit this car with so much cheap plastic.
BEFORE
AFTER
After a few days of running road tests and getting a feel for the new suspension, I noticed that at higher speeds, when driving over any imperfection on the road, I would get feedback in the steering wheel. It felt as if the car was oversteering. I knew lowering the car would change the geometry of the suspension but not to this extent. After doing some research I found that what I was experiencing was common when changing the ride height. At the new ride height, the car's existing tie rods were no longer parallel with the road which made the car want to naturally counter steer. I was left with two options; give up cornering performance by resetting the car's ride height to factory or invest in adjustable tie rod ends and work with adjustments
Factory tie rods
