posted on May 04, 2010 17:11
A Look Inside: The Rahal Letterman ALMS GT BMW M3 Coupes
By Mike Kojima, photos by Jeff Naeyaert
Thanks to our friends at Volk Wheels, the technical staff at MotoIQ had a special opportunity to get a close insider's look at BMW's uber-trick factory works BMW M3's that Rahal-Letterman racing campaign in ALMS's GT class. If you do a google search on these cars, you will not find much information on them because until now, no one that cares has gotten a really close look at these amazing machines. Most reports have pretty pictures of the cars and stuff about the "Story of Joy" marketing campaign that the cars are promoting but in typical MotoIQ form, we will take you inside like no one else has before.
The Rahal Letterman BMW M3's are a factory effort and are campaigned in ALMS in the GT category by Bill Auberlen, Tommy Milner, Joey Hand and Dirk Muller. The GT class cars must retain the factory unibody or body in white but are allowed quite a bit of leeway in their modifications. In short, these M3's are like something you might build for Time Attack's Unlimited class if you had money--a lot of it.
|This was as close as we were allowed to the engine. It could be a carbon shrouded lawnmower in there for all we know!
We will first take you through the engine since we don't know very much about it. The team's engineers were very quiet when we asked them about the engines specs and we were not allowed within 20 feet of the engines or any internal components. We do know that the engines are V8 derivatives of the factory M3 engines. They displace 4 liters and pump out 485 hp and 368 lb/ft of torque vs the stock M3's 415 hp. The stock block and cylinder head castings are used. No titanium is used anywhere in the engine under homologation rules.
Wednesday, May 05, 2010 4:57 AM
Cool stuff. I didn't see a picture of the rear of the car. I'm curious what the rear diffuser looks like now that you've mentioned the restrictions on them.
Wednesday, May 05, 2010 7:32 AM
As always, a totally badass look into a real race car. Any chance of getting under the hood of one of the LMP Acuras?
Wednesday, May 05, 2010 8:14 AM
motoIQ bringing the Euro racing flare...nice, I'm liking it...
Wednesday, May 05, 2010 8:15 AM
We were not allowed to take pictures of the rear underneath of the car or the underneath in general.
Wednesday, May 05, 2010 8:58 AM
Very impressive stuff! This article really helps me to get a feel for how complicated even the production based GT cars are in the ALMS.
Wednesday, May 05, 2010 10:26 AM
When I see racing coverage in other magazines I usually pass it up. Mike you always seem to make this stuff interesting for racing novices like myself.
Some of the big print mags are trying to copy this format which I think is good for the industry. Car and Driver's Csaba Csere titled and article in the June 2010 issue "Suck Squeese Bang Blow" or something close to that. Hrm, I wonder where that idea came from. Regardless of the title it was an interesting read. Since our electronic format offers unlimited room we'll be able to go into more detail.
Wednesday, May 05, 2010 10:29 AM
I suppose I should clarify I have the upmost respect for Car and Driver as a whole especially Mr. Csere. But as the saying goes "imitation is a form of flattery."
Wednesday, May 05, 2010 1:48 PM
I like how everyting on the car is so trick and well executed....EXCEPT for the hole for the linear pot. What the hell did they use to cut that hole? Butter knife? Looks like a hole I would cut. ;)
Wednesday, May 05, 2010 2:15 PM
I love that car.
Wednesday, May 05, 2010 3:17 PM
Wonderful car, great article and great pictures; cheers to you guys. This should really help increase the traffic problem here.
jeff- theres a couple pictures of the 09 underbody with all the panels on at http://speedhunters.com/archive/2009/09/09/car-feature-gt-gt-ultimate-bimmer-the-m3-gt2.aspx As mike already mentioned there isn't much they can do with the rear diffuser because of the regulations. From what i can tell it just angles up and meets with the rear bumper. The real thing that would be interesting is to see, is all the ducting and routing between the underbody and the actual chassis, which apparently is what their really trying to hide...
eric- how does that work w/ the branding of the products? Since they use a "BMW Power 400" is that manufactured by you guys, specificly for them, and they just slap their "BMW Power 400" on it?
Wednesday, May 05, 2010 3:31 PM
What's the purpose of the bar that's bolted on near the front of the engine bay going the full width of the car and turning down toward the ground?
Wednesday, May 05, 2010 3:45 PM
for string alignment...
Wednesday, May 05, 2010 9:03 PM
Eric, thats interesting becasue we were told that the electronics were all in-house BWM developed that had a lot in common with the OEM ECU. They told us the electronics were not third party unless they misunderstood my questions.
They were not cofortable with us looking to closely at the engine and the underneath of the car. The diffuser is just a turn up as no vertical parts are allowed. Probably seome of the reason why there are so many details to generate side vortexes.
Wednesday, May 05, 2010 10:00 PM
I'm sorry but I just have to say it, I'm in LOVE with that shift knob! it looks so... functional. I also like the idea of the removable roof and seat for emergency access, I could see it really come in handy if the car ends up on its side and it's suspected the driver compressed their spine. Great article!
Thursday, May 06, 2010 1:21 AM
My bad for the misinformation. That was the previous generation factory built V8 race cars that had the Pectel and Pi electronics. BMW Motorsport did develop their own ecu for the current generation cars. This car is still using a Pi Omega dash still however. It has the same dash as the Sierra Evo.
Thursday, May 06, 2010 5:48 PM
Very cool about the emergency crash access. They probably learned something after this nasty crash Joey Hand took a few years ago:
Friday, May 07, 2010 1:51 AM
Cool M3. Imagine what it could do without the 29.4 restrictors?
Tuesday, May 11, 2010 2:01 PM
Is that common in racecars to use a digital protractor on the steeringwheel for steering angle?
Wednesday, May 12, 2010 8:45 PM
You know with all the development NASCAR did on the COT, I'm surprised that they don't also have the removable roof. Guess they're too busy fixing races to care.
Thursday, May 13, 2010 6:37 AM
Correct on the old cars.
Correct on the dash.
PR says everything is BMW.
Some things are so small they can be hidden anywhere...
Also, you know where's Waldo. Play where's the LJB with the pictishttp://photos.motoiq.com/MotoIQ/Features/Rahal-Letterman-ALMS-BMW-M3/JEF6172/844127506_9939h-L.jpg
Tuesday, February 15, 2011 6:27 PM
The BMW "Kidney grille" feeds the engine via the restrictors as well as the long tubes that travel over the engine and through the firewall which supply the AC system and driver cooling duct.
The large side NACA ducts located above the smaller rear brake ducts, supply the rear heat exchanger. The article said the front ducts travel the length of the car from the grille to the rear diffuser while the side ducts feed the AC which is backwards.