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07302007, 06:03 AM  #23  
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The software calculates the wrong tire circumference. It does the math correct, but doesn't care about the tolerances. As always there's a european organisation that has set this standards (ETRTO): Without tolerances: [(265 x 0.4) x 2 + (18 x 2.54)] * pi = 2.10 m But according to the ETRTO standards the circumference for this dimension is only 2.04 m! My calculation is based on a calculator of a good german forum site (mforum.de) which calculates with an average between a new and an old tire. This calculates with a circumference of 2.02 m. The dates are the following: 1st: 65.3 km/h (40.6 mph) 2nd: 111.7 km/h (69.4 mph) 3rd: 167.3 km/h (103.9 mph) 4th: 221.3 km/h (137.5 mph) 5th: 264.7 km/h (164.5 mph) 6th: 303.6 km/h (188.6 mph) Don't know why the test software doesn't consider this tolerances!? Maybe this is another european specific topic. Don't know how the T&RA standards are. I will check that later if nobody else does... Best regards, south EDIT: Now I checked the US Michelin site: There it says "Rolling circumference can be calculated as follows: 63,360 divided by revolutions pre mile = rolling circumference in inches: For the 265/40ZR18 PS2 Michelin states 790 revs per mile > 63,360 / 790 = 80.202 inches = 2.037 m. So it's the same standard for the US. The circumference calculated by the software is too big... Last edited by southlight; 07302007 at 06:20 AM. 

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07302007, 06:43 AM  #24  
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BMW 335 w/PROcede V2.0: Peak HP: 410hp @ 5,500rpm Peak TQ: 420ftlb @ 3,500rpm I'm curious aswell...! :rocks: 

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07302007, 09:52 AM  #25  
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530 ftln / 6.208L = 85.374 ftlb/L. I know you were just playing around with the numbers, but I do have to doubt that one. Still, thanks for posting all your results.
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07302007, 11:54 AM  #26 
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Agreed
I don't think the hp number is unrealistic however the torque seems to be. MB is using this exact same engine to get huge power outputs in other applications. It was trial and error, it was quick and this was the only way to get even close on 060 1/4 mi time and trap. In the end I was only shooting for average reported numbers as well, not best. In this application the tool helps us conclude that there is a large under rating but does not really pin down the number exactly.

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07302007, 12:02 PM  #27 
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Right, no issue with the power number. In fact a race tuned version of the motor could probably hit 800hp easily (though it'd need a rebuild after every race). But even in that kind of application, 85ftlb per liter would be unlikely and extremely impressive.
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07302007, 01:58 PM  #28  
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07302007, 01:59 PM  #29  
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the only track DCT will succeed in Manual is with a striaght track
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07302007, 04:12 PM  #30  
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However, like others pointed out there is a reason race cars use autmated manuals, they are faster, period. With proper launch control they are faster in a straight line and faster on a track. Since DCT is a substantially better system than SMG there is no reason to believe it will not be faster on a track. After all tracks do involve acceleration (hmm maybe DCT and SMG can not work accelrating in a curve) On the insults: I'm fairly carful about that. When letting people know they have made a mistake or I disagree I almost always keep it coridial and factual. If someone really baits me I have been known to take the bait an use insults but that is rare. My post hardly deserved your unpromted attack. 

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07302007, 04:20 PM  #31  
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??? Start educating yourself about Formula One racing. Then, educate yourself on what a DCT actually is. Then learn about why they are in development for consumer cars and why the elite of the Auto industry are moving in that direction. BMW has been using SMG technology for almost 8 years, DCT are not SMG's, they are a new technology!!! Your ignorant comments were corrected by several members here. No one was brash with you, but trying to educate you on this technology. This and your other comments were uncalled for. Your clearly misunderstood about what a dualclutch gearbox is all about. Garrett 

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07302007, 04:22 PM  #32 
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Hmm, only time I find for an M3 SMG is 8.35. Are we talking about that? That was the E36 M3! Do you guys have a sportauto time for the E46 M3 SMG?
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07302007, 04:28 PM  #34 
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Unless you can execute perfect heeltoe downshifts everytime, I don't see how the manual would be faster than the SMG/DSG/DCT around a track.
In regards to the computer picking the right gear, I would assume you would be shifting for yourself with a DSG type tranny while on the track. Why would you want the computer to do it for you?
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07302007, 04:50 PM  #35  
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Look, there are a plethora of people here on these boards (and others) with different experiences and track time. Even when you track every weekend, doesnt mean your the elite of drivers. HeelToe is an art form. Just because you can do it, doesnt mean you can do it properly or even precise and certainly not every time..! Thats they key. Consistancy! FYI, the very best drivers in the world (Formula1) havn't used clutches in YEARS. These are $150million dollar cars. Garrett 

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07302007, 06:03 PM  #36  
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Before messing with the modified 335i I tried to get the base model simulated accurately. Using published hp adn tq specs the numbers don't come out even in the right ball park. Well we know BMW has under rated this car. So I tweaked and tweaked the hp ad tq figures (max values, not so much tweaking of the rpm at which the peaks occur, but a bit) and I can not get anywhere close to good agreement with published performance data. I was using this set. The best I can get on 060 and 1/4 mi are 4.93 13.55@100.8. Those numbers are not terrible, but given than NONE of the other 0X speeds are anwhere close the model is simply not performing. By the way the numbers I used to get the figures above are 380 hp and 375 ft lb!! Probably not realistic crank numbers at all. Next I tried to enter a fully custom hp vs. rpm curve based on 335i dynos showing peak hp/tq numbers at the wheels of about 275/300 (I used these results and factored in 20% extra for the rw > crank conversion). Just as in all my attempts these could not match the published performance values either. Clearly If I can't get very close on the base model it is not really worth messing around with the modified version. I suspect the twin turbos and ECU are making some interesting adjustments that result in a very odd effective tq curves during real use as opposed to on the dyno. Any other CarTest folks want to chime in, TBone? Last edited by swamp2; 07302007 at 09:31 PM. 

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07302007, 06:07 PM  #37 
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Here
I have the ME46 M3 at 8:22 and the SMG at 8:35. Maybe the "*" qualifier has something to do with this.

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07302007, 06:13 PM  #38  
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Having only driven the dual clutch GTI a bit and not on the track I can't say from personal experience...However, from folks who have driven VW/Audi DC units on the track I have heard they are very tough to impossible to "fool". Also, as I have discussed significantly in other posts, the worst performance of a good DCT system should probably be on the order of the best performance of the SMG system. Some speculation but also if you know roughly how the system works this makes "common sense". 

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07302007, 06:15 PM  #39 
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Better check the date on that M3 SMG time. Unless the e46 m3 SMG was out in 1997, then it's the e36.
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07302007, 06:59 PM  #40 
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07302007, 07:35 PM  #41  
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DCT are said to shift in about 10ms..!! Garrett 

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07302007, 08:10 PM  #42 
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SMG for the M3 came in 2002.
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07302007, 08:32 PM  #43 
O! So Sour!!
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07302007, 09:33 PM  #44 
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Ugh

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