Build - Objectives and Planning

The GRM Ultimate Track Car Challenge - Shop Class. One of our customers told us about it and immediately it turned into a must-do event. With VIR only a little over two hours from our shop, it is certainly easy to attend. And since it is so close, it is one of the tracks that I have more time on than most drivers; results include a couple of track records and the overall win in the 13 Hour in another BimmerWorld car in 2005 and again in 2008. And we have a show/track/my daily driver project car in the shop now that will be finished spring 2007, so what better way to unveil it?

The new BimmerWorld project car - 1996 BMW 320iT.  I have always had a soft spot for wagons and now we have the time to build one.  Never released to the North American market, I imported this car from Sweden after a year of searching for the right one.  We finally dug up a no-rust, no-salt car in excellent condition, and in the right color to boot!

It was supposed to be hopped up and fun, but as it always goes, the project grew until it is over the top.  To start the project, the car was stripped down to a bare shell to make sure every part of it is fresh and correct. Forgive the wheels - that is a used-up set of Sweden's finest snow tires used as a roller to get it on the container for shipping...something a little cleaner from BBS will be
the wheel of choice.

Certainly not traditional, but I think it will be an awesome joyride.  How many other cars can toss all their wheels, tires, and gear in the back, go to the track, and lap with times that would hang with a lot of pro racecars?

Engine
The sickness begins here.  I had a 3.2L US M3 low compression Sunbelt race engine in the shop we had built with no firm idea on what to do with it.  Now it is claimed.  9:1, forged JE pistons, Arrow rods, Sunbelt cams and valvetrain, Euro oilpan/pump, etc.  Full solid mounts keep it in place once the boost spools.  Now that the engine is in the car, we are completing the rest of the package.  

The turbo system is based on a Garrett GT40R, all custom built in our shop.  The manifold is a true 6-1 collector with quite a bit of effort to make the pulses hit properly for faster spooling on the track.  A Jet-Hot 2000 coating will be applied to the manifold and housing after final fitment to keep temperatures under the hood contained.

Power output will be in the 600RWHP range, reaching full boost at 3,500 RPM for track manners.

 
Driveline
The power is laid down through a JB Racing/Clutchmasters clutch system capable of living on the street, but taking the abuse of the track.  The twin disc FX-650/Street Ultralight uses one Ceramic disc and one made from a new Kevlar material - two Kevlar discs were not enough to cover the power demands and this combination should still make the clutch very drivable.  A custom Diffsonline 2.79 3-disc final drive with custom ramp grinds keeps the turbo boosted and enough lock on the tires to limit spin as much as possible.   

Suspension
Moton Club-Sports are the foundation for the track geared suspension.  Fully adjustable to take the car from a streetable ride to the precise and responsive handling required to master the track.  A full compliment of BimmerWorld and Ground Control solid components will keep the suspension in place.  We chose to go with rear coilovers for a small performance advantage over stock spring location.

 

Brakes 
To stop from 180 MPH for Turn 1, a serious brake kit is required.  A Performance Friction racing brake system with 4 piston calipers, two-piece bobbin mounted rotors, and PFC 01 pads to grab on will get the job done.  ZR-28 front calipers (used on CART cars and our World Challenge cars, as well as others) are as solid as they come with a fixed bridge design.  The stock pedals and hydraulics are retained with a few tweaks to keep them balanced and up to the task.

 
Safety 
No track car is complete without safety gear capable of keeping the occupants safe with the given car's performance level. For the touring to cover this requirement and still remain a street driver, that means a roll hoop, seats, and harnesses. A fire system nicely tucked away will keep fire away from the occupants for the time required to get hauled down from track speeds to get out of the car if the need arises.


And all this in a wagon - slick enough to avoid unwanted attention on the street, but certainly capable of being called the ultimate track car for any BMW enthusiast and enough raw power to win over even some of the die-hard American iron fans! A work in progress, but coming together nicely...