(1) Saying it's not possible to duplicate the torque curve of a NA engine with a reasonably smaller displacement forced induction engine is false. If you don't care how, skip to (2)! If you want a peaky horsepower engine, install a turbo that's way too big on your engine and you will feel the sensation of increasing torque as high as your engine will rev before the rod bolts snap. However, you just sacraficed low end torque and driveability on the street which is where 99.99% of these cars are driven. One of the first things a manufacturer does during base engine design is figure out what torque curve they desire the engine to output. Then they design the engine around that target.
The point of their turbo engines is to maximize fuel efficiency at part throttle while providing more area under the torque curve, which effectively increases performance in the vehicle. Sizing a turbo for a specific application is similar to sizing a camshaft for an NA engine in the fact that each shapes airflow characteristics which determine the shape of TQ, HP curves versus engine RPM. Duplication can be achieved.
(2) A constantly increasing torque curve through mid range is an attribute which some people like, and others don't. If that is what you desire from a turbo engine, you turn down the boost at low speed or increase the boost at high speed. It's simple as that if the original designer chose that path. I tend to enjoy the increasing torque curve myself. I'd like to see BMW and other manufacturers use turbo applications to provide just that. An M3-like car with a high revving TT 6 cylinder or a TT small displacement V8 done right would be alot of fun.
(3) You seem stuck on this idea that HP peaks much earlier than redline. It appears to me that if "redline" is 2000 RPM past peak power RPM, then "redline" should be drawn at a lower RPM. If horsepower is falling, you missed your shift.
(4) I get your point. You care more about midrange-high speed torque than low speed torque. Fuel economy is not an issue for you. You simply like to hear and feel the engine screaming at high speed because it's cool. I agree 100%.
Quote:
Originally Posted by Ateam
This shows you are still pretty naive. It is still not possible to replicate a torque curve of a V8 with a ttv6 or the curve of an I6 with a TTI4.
That was my entire point if you read my post. The fact is that the torque curve and delivery of the I6 was TOTALLY different and very linear with hp peaking at redline. The TT enines tend to have HP peaks much much earlier and then have 2k worth of dead rpms.
Like I said, some people like these low end grunt TT motors which is fine and a totaly different issue. I am not saying one is better than than other but they sure as heck are not "similar" in anythin but on paper hp rating.
Same with the m3 current V8 or the e60 m5 V10 compared to the new TT v8. Sure the new v8 makes more power but delivers it in a totally different way and they are nothing alike aside from both being in the 5-- hp range.
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