The M3 Touring and the M4 CSL are the two upcoming BMW M cars from the opposite ends of the practicality spectrum that have got fans fizzing with excitement. But if you can’t decide with one you want, the M3 CSL sedan could be just the ticket. Just like it says on the tin, or it would if the tin wasn’t de-badged and smothered in swirly disguise, the M3 CSL is the sedan version of the M4 CSL coupe we’re expecting BMW to announce in May, ahead of sales starting at the back end of the year.

That means it’s in line for a similar round up upgrades that should put even more clean air between it and the M3 Competition as there is between that car and its non-Competition little brother. While the base-spec M3 comes with 473 hp courtesy of its turbocharged 3.0-liter inline six, and the Comp version weighs in with 503 hp using an uprated version of the same S58 motor, we’re expecting the CSL to make close to 540 horses, possibly even more.

 

And since the “L” in CSL has traditionally stood for lightweight, that power is likely to be channeled to the rear wheels alone, and not through the regular M3’s optional xDrive all-wheel drive system. An eight-speed automatic transmission is the most likely gearbox since BMW currently only offers a six-speed manual on the base M3, and neither the E46 M3 CSL, E90 M3 CRT, E92 M3 GTS or F82 M4 GTS specials came with a stick-shift option. BMW’s ZF auto adds weight versus a six-speed manual on the base M3, but other CSL upgrades likely to make an appearance to undo some of that damage include lightweight carbon panels, a stripped down interior with slim bucket seats, and reduced sound insulation.

These pictures of an M3 test car captured at Germany’s Nurburgring reveal the same grille with a bigger gap between bars that we’ve previously seen on M4 CLS prototypes. But more interestingly, the car features disguise over the rear windows, which suggest to us that BMW is either planning to fit individual rear buckets, as it did with the M5 CS, or to offer the CSL with no rear seat at all (at least as an option), much like Alfa Romeo did with the Giulia GTA.

BMW hasn’t even acknowledged the existence of the M3 CSL, let alone given any indication on price, but it won’t have gone unnoticed at BMW M’s Garching HQ that Alfa charged € 176,500 (US$ 192,500) for the regular GTA and € 181,500 (US$ 198,000) for the stripped-out GTAm, compared with around € 67,000 (US$ 73,000) for the base car. Crazy money, yes, but Alfa sold the entire 500-unit run without trouble. That kind of markup tallies with the prices of previous limited edition M cars like the E92 M3 GTS and M4 GTS, which both costs twice as much as the cars on which they were based. Using the the current U.S. price of US$ 70,100 for a base M3 as a guide, that could theoretically put the price of an M3 CSL at between US$ 150-200,000, or squarely into the territory of Porsche’s US$ 161,100 911 GT3.