After we posted my article Why Don’t We See Factory Turbocharged Motorcycles?, I received a number of email from readers claiming that my ideal of a small-displacement, low boost turbocharged motorcycle engine, which would generate significantly more horsepower than current naturally aspirated powerplants, while at the same time remaining free of “turbo lag”, was impossible to achieve. Even after posting a later article entitled Direct Injection Opens The Door For More Usable Turbocharged Motors, where I mentioned the upcoming BMW 335i specifically, I still received numerous email from doubters.
Well, the proof is here, and, to put it bluntly, I was right. If you Google the phrase ‘BMW 335i dyno’, you can find numerous dyno charts that show BMW’s new twin-turbocharged, direct-injected 3.0L inline six producing it’s peak torque of almost 290 lb-ft (at the wheels!) at just 2000rpm, and carrying a nearly flat torque graph well past 4000 rpm. In fact, BMW claims this motor actually produces peak torque as early as 1400rpm, but due to the revving and clutch slippage required to start the dyno rolling, it is nearly impossible to get an accurate dyno reading at that low of rpm. Oh, and by the way, this motor goes on to make nearly 300hp at the wheels at about 5700rpm – this is no diesel powerband!
Who cares, you might ask, it’s still a cage! Well, you’re right, but this motor can still be considered a proof-of-concept for my ideas regarding turbocharged motorcycle engines. I’ve already read several magazine reviews of the new 335i, and every tester has mentioned the complete absence of turbo lag – in fact, all of them concluded that the motor felt ‘just like a really powerful naturally aspirated motor’. It is also being estimated that the EPA mileage ratings will be 19 city/28 highway – pretty good for a ~3,600lb car generating 300hp at the wheels! Isn’t that exactly the ‘best of all worlds’ motorcycle buyers are looking for – big power spread all the way through the rev range, smooth driveability, and good gas mileage?
