RMS stands for Race Marque Systems, and the name Osh Minelian hangs on the front door of this BMW tuning establishment. While I expected the supercharged 3.0-liter roadster from RaceMarque to be fast, I didn't anticipate it being this tire-shredding monster. Considering the source, however, it was none too surprising.

Osh builds fast BMWs following a very factory-like formula, which places big engines in places we in the States only dream about. Osh was first to stuff a 3.0-liter M-motor up the nose of a Z3 and later subjected a cabriolet to the same treatment. The RMS approach, however, goes beyond merely transplanting more powerful engines and extends into such peripheral systems as suspensions, brakes and electronics. "You can pretty much have M-Technic in Germany customize a new BMW to your exact specifications," remarked Osh. "It's a great idea that's unfortunately limited to European customers. Why shouldn't we be able to get the sort of thing here?" he asked.

Thus began the idea behind RaceMarque Systems, a tuning approach with an emphasis on factory-correct hardware and blistering performance. RaceMarque had more urgent plans for this Z3 than the customary 1.9-liter M44 engine it was originally fitted with. This involved a lovely lump of metal once belonging in one of the very limited-production M3 Lightweights, Number 005 of 10 pre-production cars. Irv Sherman, owner of the donor Lightweight, gave the engine to his brother Eric (owner of the Z3), as Irv was busy preparing the Lightweight for serious IMSA duty. But the Z3 still stood in the shadow of its Euro-spec Z3 cousin, which belts out a walloping 322 hp. A Vortech supercharger worked its way into the formula and rectified the balance of power. "We've been using Vortech superchargers for some time now," said Osh. "We've found them suitable for everyday driving and durable enough road-race and drag-race applications. This centrifugal-type compressor has proven to be the most efficient of the units we've tested," he added.

High-flow motorsport injectors were used to provide the additional fuel, and the DME was reworked to handle the engine's vastly upgraded capabilities. The electronic software was reprogrammed to not only deliver more fuel across all six maps but also control idle and VANOS maps (variable valve timing). The software package is of a stand-alone nature, designed to eliminate the use of signal manipulation such as resistors or additional fuel-enrichment devices.

The measured output is a terrifying 371 hp at 6500 rpm, and most of that power is available the moment you prod the throttle. Even with the helpful technology of a Quaife differential out back, it takes a delicate touch to keep the fat Michelin Pilots from breaking traction. Running a moderate 7.5 lb of boost, the Z3 was turning 12.64 quarter-mile times with 60 mph coming up in 4.3 sec. Those with a taste for the hideously extreme have the option of the RMS low-compression motor, capable of running much higher boost levels.

Though it is scary fast in a straight line, this Z3 offers more than just brutal acceleration. An RMS Stage III adjustable suspension augments the factory bits; it's comprised of custom Koni dampers up front and specially valved Koni's in the rear. RMS sport springs provide a 1.25-in. drop in the rear and a 1.5-in. lowering in front. The front shock tower mounts are M3 spec, augmented with adjustable RMS camber plates for optimum tire contact under varying loads. Crowning the engine bay is a Motorsport strut brace that maintains equal distance between the front strut towers. Larger front and rear anti-roll bars are also adjustable, allowing the driver to dial in the amount of understeer or oversteer at will.Visible between the spokes of the factory's 17-in. M3 wheels are four-pot Brembo calipers that grip 14-in. slotted rotors. These binders provide a huge and welcome improvement over the solid, 11.3-in. units of the stock vehicle.

Running gear measurements 7.5 x 17 in front and 8.5 x 17 out back; Michelin Pilot rubber, sized at 225/45ZR front and 235/40ZR rear,feel ready to take on the rigors of racing.

The car's muscle suit is pulled directly from the M-Technic closet: the front air dam and rear valance are the same pieces that will festoon the factory's M-roadster. The rear valance was modified slightly to accommodate the quad-piped RMS stainless-steel exhaust, and the rocker panels are an RMS design. The cockpit instrumentation was upgraded with the M3 cluster, and this Z3 has the same programable features as the M3 (Kombi) instrument cluster.

Now if only Osh can figure out a way to make those tires last longer.