「Tuning one of 1400 M3 CSL’s in the World」A Sequential Transmission Equipped Circuit Attack Machine
Published : 2020/08/06 23:59 Modified : 2020/08/07 00:16
An M3 CSL that laps Tsukuba in the 57 second range
A circuit attack special aiming to be the fastest tuned NA
Using the BMW E46 3-series as a base, this M3 had been tuned by the M division from the body to the engine to the chassis. The model sold as the CSL was limited to only 1400 in the world and boasted improved power and weight reduction.
It was a bit out of the ordinary to take tuning further and base this circuit spec machine on such a rare and valuable German sports car.
The CSL’s engine is a 32 6S4 type 3.2L straight 6 DOHC. There were many changes from the base M3 including carbon surge tanks and D-jetronic control. The CSL had improved specifications to 360ps/37.7kgm compared to that of the normal M3’s 343ps/37.2kgm.
Power up was increased further to 380ps with tuning work. Engine management is done by Motec’s M800.
The car sits on Aragosta 3-way suspension（F16kg/mm R18kg/mm）Because the genuine ABS system works very well, the factory ECU operates the braking system that has upgraded with an AP Racing kit. The differential is an ATS carbon LSD with a 4.1 final gear.
The tires are Advan A050 in 295/35-18 sizing. “We have also tried other tires but have found the A050 have the best balance of rigidity and high grip performance” says the owner. Wheels are Volk Racing TE37SL in 11J widths.
In order to fit such wide tires, a Flossman Auto Design widebody kit was imported and installed. “I wanted the car to be able to get to and from the circuit on its own” says the owner, so it can go from circuit to city driving with the removal of some of the aerodynamic parts.
Most of the interior has been removed and doors were replaced with full carbon pieces. Even with a one-off original roll cage installed, the weight is still an ultralight 1270kg which is even lighter than the CSL’s factory 1430kg. “The chassis is still as strong as ever, even after 90,000kg of circuit use. I can feel the quality of BMW construction there” says the owner.
The CSL comes equipped with a semi automatic SMG transmission standard. However, this car has been upgraded to a 6-speed sequential. It seems that the factory transmission needed a number of replacements after hard circuit use, hence the reason for the upgrade.
The interior of the trunk was also stripped and the fuel tank was upgraded to prevent uneven fuel distribution.
“Originally I wanted to aim for winning BMW cup races, but then I decided to go for number 1 in time attack” says the owner. Although its a rare and valuable model, the tuning work pushes this car to a higher level. It is a superfast NA machine that run Tsukuba in an impressive 57.968