Quote:
Originally Posted by CSBM5
However, I wouldn't think that a non-ZCP car would be non-competitive at all (i.e. the minor spring change and 1/2" wheel width might well be within the bounds of repeatability in testing on typical autox courses).
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And either would be better than an M5-at autocross!
Quote:
Originally Posted by CSBM5
The 6MT saves 50lbs over DCT..and I love the damping rates of the stock shocks btw
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I would certainly run the stock shocks for a year or so, at minimum. Money would go to wheels and driving schools first. Please let me know when you will be teaching up your way, Chuck. I'd like to take advantage of learning from you! Also, I am glad to hear that the shocks are well liked, by you.
The consensus is the M6 trans so far, but, to play devil's advocate: Looking at this from a statistical point of view, the DCT offers 5% torque advantage in 2nd gear (from gearing-see below). A number that probably shouldn't be ignored, considering this could be 115 ft lbs to the tire. Granted parasitic losses aren't calculated-are they similar between the two transmissions?
Can the M3 put this torque down sufficiently with 295 street tires? Or is there a traction issue as it sits?
Also, shift times are much faster with the DCT-can this be quantified?
Gearing analysis:
M6 1st gear final drive: 4.055*3.678=14.91429 ORIGINAL POST INCORRECT REAR GEAR
M6 2nd gear final drive: 2.396*3.678=8.812488 ORIGINAL POST INCORRECT REAR GEAR
DCT 1st gear final drive:4.78*3.154=15.07612
DCT 2nd gear final drive:2.933*3.154=9.250682
M6 1st Gear final drive: 4.055*3.846=15.59553 CORRECT REAR GEAR
M6 2nd Gear final drive: 2.396*3.846=9.215016 CORRECT REAR GEAR
ORIGINALLY POSTED WITH INCORRECT GEAR INFORMATION
Also, this doesn't take into consideration any torque converter torque multiplication (or slip).
That is a 1% advantage in 1st gear...meh
But, it's a 5% torque advantage in 2nd gear, with a 50 lb penalty. This should be measurable an autocross. Would you disagree?
With the correct gear information in mind, there is no significant gearing advantage with the DCT. The conclusion would be to go with the manual, which is 50 lbs lighter.
Although, one would still be able to left foot brake more effectively (arguably) with only 2 pedals, particularly with rev matching-assuming the software works properly.
OLD CONCLUSION BASED ON INCORRECT GEAR DATA:
After looking at this, the DCT looks to be measurably better to me (for autocross reasons only), even with the 50 lb penalty. Additionally, this weight is in the middle of the car, very close to CG.
Please shoot holes in this, because I'd prefer the M6, but, if the DCT is measurably better, that's the way I'd need to go...if I were to do this. Of course, if the competition package is only available with the M6...then the comp package is the way to go. Also, if there were still DCT issues, that would steer me away from that. I don't think that is the case, however. Thoughts?
Thank you Rich and Chuck for setting me straight!