Chris is a BMW mechanic who has a love for BMW Euro M Cars. He has maintained and driven BMW’s on tracks since 1986 and believes the Euro models are more of a pure sports car. His first car is a 1995 BMW 3.8 Liter Euro M5 Touring (E34) in optional Avus Blue Metallic paint with full Nappa leather Silver Gray interior and six-speed manual transmission. He sold this M5 Touring in a Collector Chassis Auction in March of this year. The second car is his 1985 BMW Euro 635 CSi M6, which is listed now.
After Chris acquired this M635 he did a more through inspection and completed the following:
- Installed new tires.
- He rubbed out the entire car with compound and a dual-action electric buffer to a mirror shine, removing swirl and some ripple. He then buffed and coated it with multiple layers of pure carnauba wax.
- Cylinder head had not been checked and retorqued. He completed that procedure which is not trivial on a DOHC direct-actuated valve train.
- He purchased an R134a AC conversion kit to upgrade the current R12 system.
- Changed all the fluids transmission oil, differential oil, and coolant.
Chris said he likes the Euro BMW M cars because they have higher compression with up to 30 hp more and lighter weight interiors. The U.S. M6 versions have more complicated and heavier AC systems as well as heavier electric seats. This M6 has manually adjustable sport seats.
The hand built M88/3 motor in the M6 is a high-revving (6800 RPM) double-overhead camshaft powerplant and is identical to the earlier BMW M1. However, the M88/3 engine differed with a more fuel-efficient electronic Bosch (Motronic 1.3) fuel injection control system.
This M635 CSi (E24) had its engine rebuilt with MaxSil Pistons with proprietary Teflon-coated piston skirts, piston rings, and oversized pins (to be honed to match rod bushings). After the engine was rebuilt, the catalyst and the entire OE muffler system were removed. A new, stainless-steel high-performance Billy Boat dual exhaust system was installed.
The core of the M6’s attraction is its magnificent 24-valve, double-overhead-cam, individual-throttle 6-cylinder engine. For a car of the Eighties, the M6 had impressive performance. It could leap from 0–60 mph in 6.1 seconds and do the quarter mile in 14.7 seconds. Top speed was limited, however, to 158 mph (255 km/h).
