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Discussion Starter · #1 · (Edited)
Here is a graph showing each gear's (1,2,3) acceleration on the roll. I stayed in each individual gear from fairly low RPMs to way up there R's. You can see that the high cam kicks in later than it would had you just upshifted from the prior gear near redline. Our cam is supposed to kick in at about 6200 or so. I understand that the motor is set up to stay on the cam after shifts if the next gear RPM is 5800 or more. This graph shows the actual g-forces you feel versus the car's speed in MPH. (Third gear shows two runs, one was on a *slight* downhill.... Also, I was not prepared to take 4th, 5th and 6th to their limits!!)

The g-force curves track the torque curve shape as expected...and also show the effects of increasing aerodynamic drag as road speed goes up.

 

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wow, this is cool. Thanks, Stan.
 

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Discussion Starter · #3 ·
>>>wow, this is cool. Thanks, Stan.<<<

You're welcome, I'm always playing around with stuff. I'm going to try measuring some 1-2 shifts to see about staying in lift without lag. The 1-2 shift is the tough one in that regard. The higher upshifts are easier since the gear ratios are closer hence the drop in Revs is lower.
 

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Discussion Starter · #4 ·
Here's another graph showing a couple of runs through the gears. You can see differences in the launch and shifts and so forth.

 

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Stan, thanks posting your findings and experiences on the Elise. And I don't just mean this thread! "Wealth of information." :clap:
 

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I also thank you, Stan.

As most of us are simply waiting for our cars, limited to maybe one test-drive, your posts are very helpful.

The next-best thing to actually drving the car... :)
 

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This is really cool, I didn't know GPS could get speed data like this, very cool:) What is confusing to me is, if the second cam gives higher torque in the 5800 rpm region, why did they not choose to have it always switch to the second cam at 5800 under full throttle. Why only after a shift? Seems odd.
Sometimes on autox courses you have to short shift out of 1st due to course design or whatever, once in second you would not get the second cam until the 6200 point.
 

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Discussion Starter · #8 · (Edited)
>>>This is really cool, I didn't know GPS could get speed data like this, very cool What is confusing to me is, if the second cam gives higher torque in the 5800 rpm region, why did they not choose to have it always switch to the second cam at 5800 under full throttle. Why only after a shift? Seems odd.
Sometimes on autox courses you have to short shift out of 1st due to course design or whatever, once in second you would not get the second cam until the 6200 point.<<<


Oh my logger can do way more than that. I autocrossed yesterday and it drew me course maps, lines through turns piles of numerical data... I also logged two National level guys duking it out in the same CSP Miata. Man the logs show that those guys stay at top speed through many portions of the course. I could see many areas where I was too timid after seeing what those guys were doing. They didn't brake AT ALL in some areas I did.

I can overlay their runs, compare the lines used, see if that downshift or alternate line helped or not you name it. When you overlay their speed traces and index that to the course map you can see that driver A pulled ahead in one segment and then fell behind in another. And you can see why this occurred. Since you can divide the course into segments whereever you want this is quite useful because the total time for the run does not matter. That is if you blow the finish or middle for example you can still get great data for other portions of the same run.

On the cam thing...remember that the Elise is fastest on the high cam. It's okay but much less strong below that point. In yesterday's event I could not be on cam in many areas that would have helped out. Think of the small cam as being a low revving economy car type of option. The high cam is more race oriented. The engine would have less of a step and be faster if they made the small cam more capable in the 4-6000 range. But the cost would be a weaker 2-3000 range. You can see that the Elise and ZO6 are very different. The former can be floored a great deal of the time in autocross while the latter can seldom be floored.

When I finish installing the logger it will record more stuff such as RPM, speed of each wheel (ABS sensor derived) exact steering wheel position, pedal activity (0-100%) while being able to sync this stuff with up to 10 video camera angles both in car and from the side of the course. Basically any car or driver activity you can think of and come up with a sensor for. If you put one of Randy's Chase cams on the top of the helmet you could record exactly where the driver was looking which is super important in autocross. Maybe add a camera on each side to gage distance to the cones and perhaps a grille cam and a foot/pedal along with a view through the windshield showing the course and steering activity.
 

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"Stan's High-tech AutoX School" I can see it now. You're talking about the most comprehensive data-logging available. Wow! How much was this system and how hard is it to install? And how does it measure other cars? I assume you have to put it in their car.

For a guy like me starting off, this would be an absolute gold mine of data and teaching as long as I had good comparables. I'd love to see my data vs. you, or Perry and Brian. It also could be used to compare the capabilities of different suspension setups and different tires. Unbelievable!

Very interesting, Stan. Thanks
 

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Discussion Starter · #10 ·
It's just a race technology DL1 setup, about 8-900. It's not hard to install at all and the basic car maneuvers require no install. Just attach the box and GPS antenna and plug into the power socket.

Here's a portion of what you can crunch with the data. I discovered a bunch of things already and can see some driving options that might work better for me as well as some neat things about what the Elise likes at certain times. I am still comparing myself to two National level guys I logged in a CSP Miata on Hoosiers. I can see that those two are much more aggressive in the slalom transitions than myself. And they don't brake as much or as hard. Different car of course but still it's interesting stuff. All the graphs you decide to use update live as you go through a run after the fact on the PC. After a few more events I can see myself using a certain set of views or charts to see where I can try to find time.

 

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Stan......Your posts are great, but they would be much easier to read if you would set your margins. I get dizzy scrolling left to right. Thanks. Ron
 

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Discussion Starter · #12 ·
>>Stan......Your posts are great, but they would be much easier to read if you would set your margins. I get dizzy scrolling left to right. Thanks. Ron<<<

Thanks Ron...in this thread the "margins" are set by the width of the screen shots. I tried reducing them in size, but then they are no longer legible since they are 1:1 So bear with me if possible. Photos are much more downsizeable in general. I'll see what I can do to help out though.

Here is another one showing the Elise and some Miatas...check out how one driver NAILED the Chicago box. And that the Elise driver (me) uses the brakes too often and too hard.

 

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That last graph is stunning! You can see right where you could get faster. Can you see them real time? Otherwise how are they going to help you during a competition? I suppose they'll help anyway as a look back. Neat stuff.

On that last one-is that with the GPS just sitting in your car, or is that wires in?
 

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Discussion Starter · #14 · (Edited)
>>>That last graph is stunning! You can see right where you could get faster. Can you see them real time? Otherwise how are they going to help you during a competition? I suppose they'll help anyway as a look back. Neat stuff. <<<

Real time as in while you are driving? There is a real time mode if you load a laptop into your car and have a helper. They also have a digital dash coming out that plugs into the gizmo. Basically the thing records onto compact flash cards like many digicams. You unplug a CF from the logger and then plug it into you laptop directly or via a USB car adapter again just like a digicam. So if you finish a run, you can have charts and all that maybe 30 seconds later. So there is plenty of time to figure out what to do for the next run. You can also figure out segment times if you blow a run since much of it is still good data. To do a run you just hit one button, when you are done you hit it again. The button and status light is on the unit. Or you can remote wire a start/stop button and light so it's more convenient. A 64 mb card (22 bucks) holds about 3 1/2 hours of data. The unit has no settings..just start/stop logging. No display - it doesn't need one. You give it power (no logging) a few minutes before you start running and it finds the GPS satellites. The more it finds the better the accuracy.

>>>On that last one-is that with the GPS just sitting in your car, or is that wires in?<<<

I'm just using that gummy stuff - blutak. It holds the logger down, as well as the GPS antenna which looks like a small PC mouse. Power comes from the power socket in the car. For a fancy setup it needs more wiring and sensor install efforts depending on what you are trying to do. I'd love to see the steering and pedal activity during that Chicago box effort. Tie that to video and you'd have yourself a new technique to learn. Not at the event, this would take time. Things like left foot braking are being used. The install into the Miata took like a minute.
 

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Discussion Starter · #15 ·
>>>On that last one-is that with the GPS just sitting in your car, or is that wires in?<<<

Oh yeah...by the way... I had the gizmo with me for the Hershey thing!! But the surprise closed event status messed me up as I had to get a way in to the event arranged which took some finnagling as they told me it was impossible. So I lost time to play around with cool stuff like this gadget. Otherwise we could have tried the thing out in both of our cars and compared, and likely Brian/Perry too.
 

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Hi

here you see another graph produced by same or similar instrumentation.

Would be very interesting if Stan can show us for comparison the corresponding diagram for the Toyota- Elise.

Please also inform about T- air, barometric pressure, tyres, slope of the test track, and wind force.( no cheating please :) )

Ruediger



PS
Nearly forgot to mention that this is a S2 with an Honda K 20 A engine:)
 
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