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      05-22-2013, 03:05 PM   #66
Remonster
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Quote:
Originally Posted by Boss330 View Post
Interesting article on the McLaren MP4-12C on the dyno and with power curves.

http://www.edmunds.com/car-reviews/t...no-tested.html

As can be seen on that engine, it's possible to combine high end power, high rev limit and turbocharging.



Interesting overlay of power curves for the McLaren, Porsche 911 GT2 RS and Lexus LFA:

It is possible to combine high end power, high revs, and turbos but to do so you need bigger turbos, bigger piping on the intake side, etc. to flow enough air at those high RPMs and this usually results in a little extra lag. I've seen real world drivers post complaints about the turbo lag on the MP4-12c on Rennlist and 6speed and other forums. I've never been in a 12c so I can't say how bad the lag really is, it's likely they're just being overly picky or trying to compare that car to the insanely responsive 458 Italia, but the main trade off for a high revving turbocharged car is turbo lag. That article also mentions that the McLaren made peak power at 7,700RPM despite its 8,500RPM which is a pretty good power curve but you can see that they still sacrificed a little bit of top end power in order to keep the lag to reasonable levels and to gain a little more power in the midrange.

BMW could get around this by having two (or more) differently sized turbos like the Mark IV Supra, M550d, etc. so I'm very interested to see what this S55 motor turns out to be like.

btw, here's one owner's review of his MP4-12c; "- Throttle response leaves a little to be desired. - TURBO LAG! Below 3000rpm the small engine does show through. You really have to be above 3000rpm all the time otherwise it feels like I am driving my smart car. There really is virtually no get up and go at all compared to my similar cars."

Last edited by Remonster; 05-22-2013 at 03:11 PM..
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