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      07-30-2007, 08:42 PM   #23
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Quote:
Originally Posted by T Bone View Post
The software has been around for years so I imagine they have an extensive trial-and-error system couple with some good models.

For example, I emailed the author about the M6 model when I plugged in the numbers and it didn't work out. He suggested playing with the shift times and bang the new numbers were consistent with real world observations. And the parameter adjustments were not unreasonable (for example, in my case, I had my shift times at 0.08 instead of the 0.5 seconds for manual shifting.
thanks. it sounds like you and swamp find it accurate enough to spend time with it. i'll order a licence.
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      07-30-2007, 09:23 PM   #24
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I think a simulation is a simulation and while it can provide an accurate estimate to the numbers of performance it can't estimate the experience. It's fun to compare an uber sports coupe to a middle engine super sportscar on paper and even more fun to compare them on a track, but in reality they don't compare. Even if the M3 can keep up with a 50k dollar plus sportscar from Audi I think I would rather be in the Audi with monetary issue out of the picture. If you deny this logical then you are essentially saying a 24k dollar civic si, with mods, is a better buy than a M3 if it can keep up with the new M.
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      07-30-2007, 09:28 PM   #25
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Agreed

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Originally Posted by bobbo View Post
I think a simulation is a simulation and while it can provide an accurate estimate to the numbers of performance it can't estimate the experience. It's fun to compare an uber sports coupe to a middle engine super sportscar on paper and even more fun to compare them on a track, but in reality they don't compare. Even if the M3 can keep up with a 50k dollar plus sportscar from Audi I think I would rather be in the Audi with monetary issue out of the picture. If you deny this logical then you are essentially saying a 24k dollar civic si, with mods, is a better buy than a M3 if it can keep up with the new M.
I agree, there are some things almost intagible and sublime about some cars. You can not reduce a car to a set of numbers. However comparing a E92 M3 to an Audi R8 is abit more reasonable/justified than comparing a seriosuly modded $20k economy car to a true sports or GT car. The Audi R8 is a wonderful car with very impressive performance. For me is comes down to AWD, the looks and the price - I don't like any of them.
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      07-30-2007, 09:31 PM   #26
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I personally would "hit" an R8. However, for the money, I would just move ever so slightly up to the 997tt.
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      07-30-2007, 09:41 PM   #27
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Quote:
Originally Posted by bobbo View Post
I think a simulation is a simulation and while it can provide an accurate estimate to the numbers of performance it can't estimate the experience. It's fun to compare an uber sports coupe to a middle engine super sportscar on paper and even more fun to compare them on a track, but in reality they don't compare. Even if the M3 can keep up with a 50k dollar plus sportscar from Audi I think I would rather be in the Audi with monetary issue out of the picture. If you deny this logical then you are essentially saying a 24k dollar civic si, with mods, is a better buy than a M3 if it can keep up with the new M.
hmmm...for designers simulations are an essential tools for performing sensitivity analysis and predicting the performance of alternatives to see if requirements are met and so. for the rest of us, poking around a simulation package is simply entertaining, and even educational. at the very least, it seems to serve as a relevant tool on this forum to seed good discussion. and that's great.
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      07-30-2007, 09:52 PM   #28
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Quote:
Originally Posted by lucid View Post
hmmm...for designers simulations are an essential tools for performing sensitivity analysis and predicting the performance of alternatives to see if requirements are met and so. for the rest of us, poking around a simulation package is simply entertaining, and even educational. at the very least, it seems to serve as a relevant tool on this forum to seed good discussion. and that's great.

Yes, I absolutely love playing around with the settings to see what it does.... Not bad for a few dollars.

BTW, I would never buy a car just for acceleration but as a fellow car nut, you can model a lot of things and then relate it back to your own experiences.
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      07-30-2007, 10:25 PM   #29
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Quote:
Originally Posted by lucid View Post
hmmm...for designers simulations are an essential tools for performing sensitivity analysis and predicting the performance of alternatives to see if requirements are met and so. for the rest of us, poking around a simulation package is simply entertaining, and even educational. at the very least, it seems to serve as a relevant tool on this forum to seed good discussion. and that's great.
Yup that's why I said it's good fun.
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      07-30-2007, 10:41 PM   #30
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Quote:
Originally Posted by T Bone View Post
Yes, I absolutely love playing around with the settings to see what it does.... Not bad for a few dollars.

BTW, I would never buy a car just for acceleration but as a fellow car nut, you can model a lot of things and then relate it back to your own experiences.
the obvious problem is that since you haven't written the code, you don't really know what it is doing. and it could simply be garbage in garbage out, and one might simply be smoothing out the garbage while calibrating to real world data, but it's still fun.
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      07-30-2007, 11:08 PM   #31
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Swamp

Sounds like drive train losses are a bit higher in 3rd gear and a bit lower in 4th gear, since the aero calculations should be identical.

I've got a bit of work to resolve an intake design issue on the car. Once I do, I'll send you some new numbers with some decent intake flow and improved exhaust.
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      07-30-2007, 11:18 PM   #32
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jworms, we all belong to a fairly elite club of auto enthusiasts. Even though there are things about the M3 I don't like (styling, comfort, crappy manual shifts, offset location of pedals) I still appreciate it for the excellent car that it is. I've run with some nice E46 M3's at Lime Rock and Watkins Glen on track days, and have driven one on the track. They are fun impressive cars. The new M3 has been criticized as not being as raw as the E46. I actually think that once it arrives, you'll find that it's a different type of raw that will grow on people. The RS4 had a pretty rough going of it when it arrived too.

I'll follow along on this board from time to time, because I appreciate the M3. And when people make stupid statements about Audi's, I'll probably correct them about that and have people pissed off at me.
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      07-30-2007, 11:54 PM   #33
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Hanging out

Quote:
Originally Posted by RI_RS4 View Post
I'll follow along on this board from time to time, because I appreciate the M3. And when people make stupid statements about Audi's, I'll probably correct them about that and have people pissed off at me.
Please stay! I think I speak for most of us in saying we enjoy your honesty and your perspective, not to mention your technical savy. Please help keep us in line when we talk crap and do the same to the Audi fan boys who seem to feed off stirring things up over here.
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      07-31-2007, 06:21 AM   #34
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Quote:
Originally Posted by RI_RS4 View Post
And when people make stupid statements about Audi's, I'll probably correct them about that and have people pissed off at me.
Why do you feel the need to protect your car like that?

I just couldn't see myself scouring the Audi boards just looking for some bad comment that someone made. What is that all about? Who really cares?
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      07-31-2007, 09:21 AM   #35
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I for one appreciate his input
I've learned more here than I could hope to by jus googlin and searchin on my own.
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      07-31-2007, 11:58 AM   #36
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Missed

Quote:
Originally Posted by Epacy View Post
Why do you feel the need to protect your car like that?

I just couldn't see myself scouring the Audi boards just looking for some bad comment that someone made. What is that all about? Who really cares?
I think you missed his point. He is saying when Audi trolls come over here and spout nonsense he is going to correct THEM. Sounds totally unbiased, not meaning he does not have his preference to own an RS4 right now, just fair and unbiased.
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      07-31-2007, 12:32 PM   #37
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Quote:
Originally Posted by Epacy View Post
Why do you feel the need to protect your car like that?

I just couldn't see myself scouring the Audi boards just looking for some bad comment that someone made. What is that all about? Who really cares?

Wow, that's a projection if I ever saw one.

I look at this board because I like the M3 and am interested in hearing about it, whether or not I own one. I do not "scour" other boards, but this one seems to have some good information and relatively adult members. I have some knowledge about Audi's in general and some unique knowledge about the RS4. If you don't like it, feel free to pass right by my posts. I won't be offended.
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      07-31-2007, 06:00 PM   #38
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Quote:
Originally Posted by RI_RS4 View Post
Wow, that's an observation if I ever saw one.
fixed...
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      08-24-2007, 02:04 PM   #39
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Improved M-DCT simulations

Thanks to lucid for triggering my thinking on a small error with the M-DCT sims.

Why were the time periods of deceleration too long with the tweaked M-DCT runs?? It was obvious. Not sure why I missed this - the time step is one of the most important things in a time domain simulation. The time step must be small enough to capture the actual physics (time scales) of the event! The std. time step in the software is .05 seconds. You typically get changes in in results only in the second decimal point or after by bumping the time step down drastically (say by say a full order of magnitude). Using a smaller time step for a typical AT or MT just gets you no better results and takes a lot longer - totally not necessary. But now with a .01 s time step I have some much better sims for the M-DCT! I did try much smaller time steps as well but again typically only changes in the second decimal place for most relevant results. I'll have to update the main post on this topic as well!

You'd think a guy in this business would get convergence...Oh well really happy to have some better figures. Not only do we see better performance but the results make more sense and there is sound physical reasoning as to why these sims are better. Thanks again to lucid for the "trigger" to get me on the right track here.
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