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      08-22-2011, 10:56 PM   #188
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Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

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Originally Posted by img View Post
DCT will slaughter any 6MT both in trap speed and elapsed time.

Don't buy Sticky's BS that trap speed is all horsepower and isn't affected by shift speed or gear ratios. PG put the nail in Stickky's coffin beyond any shadow of a doubt with this research:

Here's a video PG put together for me just to demonstrate what happens to near equal cars:
So no matter how you look at it, the 6MT had every advantage in its favor. Yet in spite of it, look what happens.

In the race above, the DCT demolishes the 6MT in every way possible. In spite of a horsepower and density altitude disadvantage, the DCT beats the 6MT by 15.6+ car lengths, 1.364 seconds, and 8.955 MPH. So the next time you see somebody try to compare a DCT to 6MT and tries to tell you they are equal, just show them this video.

For more proof, look at this vBox Racer video. The last race in this video is Drew's car vs. mine racing 60-130 MPH. Even though I have more HP that Drew, I get slaughtered in the race just like Zim got slaughtered in the drag race above.
Wow not even sure where to start here. In short this is pretty much all incorrect. It looks like we will probably get way off topic but I can't let this rubbish slide.
  • Assuming good traction, good launch, etc., power to weight is what determines ET and trap speeds. I don't often side with Sticky but he is essentially right here. Everything else is a much smaller factor.
  • Sure if you have a crappy driver in a MT who takes 0.6 seconds to shift, yes this will hurt your ET and trap by quite a lot but a fast shifter can shift a MT in closer to 0.25-0.3 seconds and we should assume this is happening to give a MT a fair shake.
  • I've been a strong and long term proponent of DCT over MT for performance reasons. It does matter but it does not matter nearly as much as you and your referenced info claim. According to both simulations and empirical test results DCT (in a stock M3) is good for about an equivalent of 15-20 hp. That in turn is only good for a few tenths in the 1/4 mi.
  • The advantage of DCT is almost entirely due to shift speed advantages, not gear ratio differences. This also has been proven out with simulation quite well. Where DCT gear ratios shine, that is not related to drag racing, is coming out of a corner at an equal speed to a MT in 2nd or 3rd gear. The overall ratios are quite a bit higher and thus the DCT will come out of corner much harder and pull ahead.
  • The cars that were compared in this "re-enactment" simply DO NOT have anywhere close to the same power. I don't care what the dynos say, different dyno, different conditions, different days, different tunes, different operator, etc. How many differences do you need? The DCT car in this case had substantially more power, period. If the two cars actually had 586 and 594 hp respectively their 1/4 times would be within 0.3 sec ET and 3.5 mph trap, accounting for the DCT advantages and assuming a 0.3 second shift time.
  • It takes about a 75 hp difference and the DCT->MT disadvantage to provide a true 9 mph trap speed difference.
  • Even a really terrible shift time of 0.6 s in the MT would only account for about half of the observed ET differences here. Again... apples to oranges, period.
  • Have a look at some stock M3 quarter mile results differences between DCT and MT. Here we have very high confidence that both cars will be making VERY close to the same power.
  • If you really think this is a true apples to apples comparison of DCT vs. MT then I have some great business ideas centered around selling sand to some Arabs that we should really discuss in detail in person.

E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK |
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