Back in the 1970s, a collegian named Steve Dinan kissed off an engineering career to bust his knuckles pumping up BMWs. One of ?his turbocharged Ultimate Driving Machines first laid a patch on these pages in 1988, and since then, we’ve tested eight Dinan BMWs, more or less melting for them all.
The S3-R M3 is emblematic of the type of audacious tinkering we expect from Dinan Engineering’s workshop in Morgan Hill, California—and the kind of prices. Order everything from Dinan, including the engine, suspension, brakes, wheels, fries and a Coke, and the bill comes to $47,836. That is, after you’ve purchased a $60,575 BMW M3 coupe and $1806 in new tires.
Yes, it’s just a wee bit spendy, but this is no casual slap-on of carbon-fiber flounces and plastic galloons. (Dinan offers at least four variations on this theme, from the highly souped-up S3-R to the cosmetic-only S.) The M3’s stock 4.0-liter V-8—a Valjoux 25-jewel chronograph among car engines—is yanked right out, its major organs eviscerated. This, ahem, voids BMW’s warranty, but Dinan takes over and ensures its work for the same four years or 50,000 miles. Dinan, which also builds BMW’s Daytona Prototype racing engines, then repacks the block with a billet crank, forged pistons, and lighter connecting rods. In the event, the bore widens by two millimeters, to 94, and the stroke lengthens by 7.8 mm, to 83.
Thus, in the $31,234 engine portion of the S3-R makeover, Dinan adds 609 cc of displacement, rechambering the engine into the car as a 4.6-liter. Dinan also bores out the throttle bodies (for greater airflow) and fits a smaller, lightweight crank pulley to lessen parasitic power loss from the water pump, the A/C compressor, and the alternator.



