I’m sure that you are all somewhat familiar with this beautiful piece of engineering -the Rahal Letterman Racing BMW M3 GT2…. And lucky for you, BMW agreed to let me get under the skin of the GT2 during my recent trip to Rahal Letterman Racing a few weeks ago.

I’ve been following the development of this car with some interest since the racing program was first announced and made sure that John Brooks took tons of snaps of the car at Sebring earlier this year. The debut of the new racing machine went quite well all things considered. Although both cars DNFed, Muller and Milner pushed it up to 2nd place before the M3 had to stop with a drive train issue.

I got to see the car only a few weeks later at the Long Beach ALMS race. By this time we’d already arranged permission from BMW to shoot the Driver’s Experience Films with Tommy Milner. In only its third race, Milner and Muller managed to nab the car’s first podium spot with a third place result…. A first place in  class was only a matter of time and this happened on August 16th with the cars sweeping the first two positions in GT2. The future certainly looks bright for the M3 GT2s!

So let’s now take an exclusive, detailed look under the skin of this beautiful race car.

Let’s start our tour inside the cockpit. The first thing you’ll notice in this shot is how far back and low the driver sits. A mockup of the factory dashboard is still in place, but the instrument panel has been extended backwards quite far.

This shot from Sebring shows the “back and low” seating position.

The seat on this car is much more that a regular racing bucket. It’s actually a rigid, partial survival cell of sorts and allows for the driver of the car to be lifted out of the machine in case of injury.

In fact, the M3 complies to all the latest safety standards… the carbon fiber roof is actually removable…. see the circular marking in the front center of the roof?…

…This is a perforation that can be punctured to allow for the roof to be peeled back for driver extraction. You can just make this out in front of the Dunlop Logo…

The center bar along the top of the windshield frame can also be unbolted, again to allow for easy access to the driver.

Ok let’s look more at the controls…

I thought it would be interesting to take a few photos right from the driver’s POV, so sat in the car to get this shot…. most of the switches on the wheel are pretty self explanatory.

To the right of the sequential shifter, is another bank of switches, as well as the radio…. to the left of the shifter, is the air conditioning duct. ACO rules state that the cockpit temperature on closed cockpit cars must not exceed 32 C so some engineering effort has gone into the development of this system.

Controlling cockpit temperature is also the main reason that the cockpit has been partitioned in half. It’s a smaller volume of space that needs to be cooled, so it’s going to tax the air conditioning system less. Clever!

My patent leather loafers look a little out of pace on the race pedals!

So best to show a picture with the shoes out of shot… that brake pedal looks rather well worn…

There are quite a few cables running every which way in the passenger area. One of the car’s mufflers is mounted under a tunnel marked by the silver insulation. They’ve needed to be channeled into these tunnels to allow for the M3’s extremely low ride height. There’s no room for any mufflers under the car.

In an effort to control heat, the exhaust pipes are place inside a insulation channel… you can also see the intakes for the rear transaxle oil coolers.

The air runs through these large ducts into the rear of the car…. you can see that much of the old production shell unibody has been removed… Minitubs have also been installed to clear the massive race slicks. Talk about precise and clean packaging!

Sandwiched between the unibody and the fully bellypan at the back of the car is a custom designed Xtrac 6 speed sequential gear box. It’s rear placement ensures optimized front/rear weight distribution.

The hot air then exits from the rear oil coolers out of the back of the car.

There’s no rear diffuser under the car, but the full bellypan does slope upwards under the rear bumper to create some under-body downforce.

Interestingly, the front third or so of the bellypan is made of steel… This acts as super-low ballast for the car and keeps the center of gravity as low as physically possible. Also very cunning….

The car has full race, double A-Arm suspension front and rear.. there’s no sign of any Macpherson struts to be found here! Check out how the wheel wells have been sealed up very tight… This is to control the air inside the wheel wells and the engine bay.

Up front, you can see the two 29.4 mm restrictors which restrict the 4L V8 engine to “less than 500 hp”…. That’s all the team would tell me!

At Sebring the car was running yellow lens covers…. again as per ACO rules, prototypes run white headlights, production cars run yellow lights… this helps to differentiate them during night racing.

By the Long Beach race the lights themselves were yellow.

Although based on production units, the lights are up rated for the extra illumination needed for night racing.

Rims are by RAYS with special bespoke rubber being supplied by Dunlop. Also note how the air is expertly extracted from the wheel wells…

Some engineering effort has be put to the passage of air through the front radiator.

Here’s a closer look… the ducts running over the engine feed the air conditioner….

A detail of the same view which shows the air restrictor veins running to the engine’s air box…. it’s very tight packaging!

You can also get a feeling for just how far back the engine is mounted… There is a lot of room between the radiator and the front of the engine…. it’s also very, very low in the chassis…

One characteristic about the BMW M3 GT2, that a few people have mentioned to me, is that it’s a much larger car than the Porsches, Ferraris and Corvette it completes against. This means that it needs to punch a larger hole through the air than its rivals and therefore suffers from a lack of top speed. This is something that the ACO and ALMS will have to balance out over time with the use of weight ballast and restrictor changes to even out the playing field between the various cars.

If you guys live any where near Road Atlanta or Laguna Seca please do come out to have a look at these great racing cars. You won’t be disappointed!

… Catch this this glorious moment of GT racing while you can!….

Special thanks to BMW, the NFS marketing team and Rahal Letterman Racing for their help in the creation of this story.

:Rod Chong

BMW Features on Speedhunters