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      10-26-2007, 12:42 PM   #89
swamp2
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Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

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Quote:
Originally Posted by GregW / Oregon View Post
Didn't see this posted yet. Some snippets--

- Each cylinder has two injectors, one port and one direct
- Electrically variable titanium intake valves; hydraulically variable steel exhaust valves (lift stays same on valves)
- Upshifts take 0.1 seconds
- "'The goal is not to make a BMW M3,' Yaguchi said, though many people will see it as such. 'The M3 is fun for a realy good driver, but if you're not a really good driver, int's not fun,' he said. 'This is a car everyone can enjoy; with this dcar you skill level doesn't matter.'" -- Great!
- "This one (suspension) is softer than the previous M3's...but, it is a tradeoff we could live with."
- "Lexus cleverly chose to reveal its IS F just before BMW revealed its M3 (sedan). Or was that pure coincidence? In either case, everyone's stories about the Lexus IS F will come out before other stories about the M3. This will allow people to view the IS F separatels as a sports sedan unot itself. In such a context it is an unbridled success. Against the M3, we'll have to wait and see."
Greg, thanks for this very useful information. Some very nice high tech details used in the car indeed. The part I don't buy at all is the easy to drive part. This is one thing all the reviewers have been ranting on and on about with the M3. Oh well back to the (or my...) conundrum, as I'll call it.

The most useful tidbit I noted for the "debate" at hand was the transmission performance. I already gave the IS-F the benefit of the doubt in previous simulations and have now performed a bracketing exercise. These two simulation results below show on the left: The IS-F with claimed weight and power specs but with the standard shift times from CarTest over ridden with a .1 s shift time (very impressive!). The results on the right are the same but I used some very optimistic (probably down right unreasonable values - but like I said - "braketing") mechnical tranny losses (5% as opposed to the default of 8%, and the manual value of 6%), torque converter losses are 1% (std. value is 3%) and lastly maximum transmission slip losses are set at 8% (default 15%). This is the max. extra loss during times the trans is calcuated to slip, not the loss when well hooked up.

What did I learn? Sure you get quite a bit better performance with a better tranny (obvious). In fact now 0-60 you just barely get to the worst magazine figure 4.74 vs. 4.8. For all of the other results I still can not touch the C&D results. I even continued to push harder using even "magically" low loss results for the transmission (that is the 2nd image below). I still could not touch the reported 0-100, 1/4 mi nor 0-150 results.

My conclusion still stands something does not add up:
1. Stated power/torque
2. Weight
3. Transmission ratios
4. C&D for sure and most other mag. results

The last possibility is that the C&D car was a sleeper (a new and definite possiblity - this has been done before). I would LOVE to have a dyno result for that particular car vs. the reported dyno results in this thread. That would likely end this entire debate.

I also posted one page that covers most of the inputs other than weight, dimensions, gears, power, etc. specific to each car. Pretty impressive inputs and physics captured by the software eh? (Note: no worries on all the blank hp entries, I am just using the curves calculated by CarTest which looked reasonable enough).
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