06-06-2007, 03:59 AM
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Senior Club Cobra Member
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Join Date: Aug 1999
Location: Ellington,
CT
Cobra Make, Engine: Classic Roadster 351W, T5, Red & White
Posts: 3,478
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Not Ranked
BMW: Why a V-10 ?
From Business Week.com:
"Nothing quite like a 500-hp V-10 muscle motor stuffed into a mid-size sedan! This is the modern German big-bucks version of the mid-'60s Detroit muscle car, which works quite nicely for Audi's awesome V-10-powered S6 as well.
Why a V-10? Elmar Schulte, BMW's engine development manager, says, "We wanted five liters. The ideal cylinder displacement is 0.5 liter. To get five liters, we needed 10 cylinders." Uh, Okay.
One key credo of BMW M is high-rpm, so this V-10 is engineered to rev eagerly to its somewhat astounding 8250-rpm redline with some small sacrifice in low-end torque…which, trust me, won't be missed. Light-weight reciprocating components are used throughout, which also helps reduce total vehicle weight and balance front/rear weight distribution to near 50/50. There are three power and throttle-response settings: the P400 default mode (for valets and your son's prom night) caps the engine's horsepower at a mere 400 and gives normal throttle response; P500 unleashes all 500 horses with quicker response; P500 Sport (for track work and New York parking garage attendants) provides full power with even quicker response.
BMW's Valvetronic system, which controls fuel/air intake via valve actuation without a throttle, is not (yet) developed for high-revving engines, but this M V-10 does use double-VANOS variable camshaft control on both chain-driven intake and gear-driven exhaust cams. And, like all M engines, each cylinder has its own electronically controlled throttle. Its ultra-high 12:1 compression ratio is enabled by an ultra-quick ionic-current system that senses knock at each spark plug and retards ignition timing of individual cylinders to prevent it. "
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2014 Porsche Cayman S, 2014 M-B CLA 45 AMG,
Unkown:"Their sweet lines all but take my breath away, and I desire them as much for their beauty as for their use "
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