He did ask if he was right. The part of the quote you cut off. That would be juvenile, like the AP that seems to reshape all quotes to make people look like asses or heroes.
Bill

Christ ladies, put the handbags away! We are all suppose to be working towards becoming professional Engineers! This isn't how you deal with the feeling of being threatened because someone elses todger is bigger than yours, is it! Save it for the competitions! If you are at the same competition and do a faster time than them in an acceleration run, then thats all you need to do!

The SAE considers the main US event (Formula SAE) to be the "world championship," so the "world's fastest car" title would probably go to the car that scored the most points in the four dynamic events (not including Fuel Economy) at that competition. Everyone should know that there is much more to winning FSAE than having a fast car.

Comparing acceleration times at different locations is silly. So is using acceleration time to judge how "fast" the car is, or even how good the engine is.

Adding more fodder to the fire...

that says 3.635 if you can't read it

Just to rain on U of M's parade, i'll go out of my way to point out that the above time is from this year's Goodyear Shootout, where the accel event was 75 yards (instead of meters), I understand. (6.5 meters shorter than an FSAE accel event).

As soon as we saw the times, we thought that the course was short. But, NC State won accel at East with a 3.95, and ran a 3.90 here. It's not everyday that somebody runs under 4 and only gets 60 points.

To back up flavorPacket's assertion, it should be noted that we did a significant amount of testing with 3rd gear launches with no gearshift during the run. In those cases, we had the engine hitting the rev limiter on average .08s after crossing the finish gate, which works out to about 2.5 m distance past the finish. In our first accel run at the shootout, this no-shift strategy resulted in us hitting the rev limit 3.67 secs after launch, according to logger data. That's .05 sec short of our accel time. which works out to rev limit coming about 1.6m short of the finish gate. Had the course been a whopping 6.5m short of a true accel run, we would have never even come close to the rev limiter.

For the record, our data shows a 0-60mph time of 3.07s. Nicht schlect.

In addition, Michigan State posted a time of 4.025, a bit off their FSAE West accel winning time of 3.894.

I'm willing to bet the the people at Goodyear know the difference between meters and yards. Our data shows it. Our competitors times show it.

What timing system was in use? Further up the thread you can see some data for the effect of transponder timings rather than beam.

Regards, Ian

Looking at the times from goodyear from a statistical standpoint, red flags are raised for me when I compare the number of teams running under 4 seconds at 2007 East and West to the number that ran under 4 at goodyear.

These figures all take into account the number of teams that actually had a score for acceleration, not the number of teams registered at the events.

07 East - 73 teams competed, 2 teams under 4 seconds.

07 West - 45 teams competed, 6 teams under 4 seconds.

Goodyear Shootout - 14 teams competed, 6 teams under 4 seconds.

Based on these stats, it would seem to me that one or more of the following conditions would have to apply at goodyear to produce these kinds of times. Either the track surface and conditions were amazing, and everybody was hooking up, everybody who came had perfected their accel runs prior to goodyear , the event only hosted the fastest teams in the nation in acceleration, or the track length/timing were messed up.

Having driven there and watched accel there, I can rule out the surface and conditions being amazing for the accel event, I didnt see anybody getting a fantastic launch. The surface/conditions were no where near the conditions at West, where the tires were piping hot, and people were hooking up so hard it made the event look easy. As far as everyone perfecting their accel runs, we all know it would be highly unlikely that everybody who competed had their accel nailed down. Although there were some very fast teams at goodyear, in no way was it a collection of the fastest accel teams in the nation.

This leaves the possibility of the timing/length of the track being screwed up. Everyone had to use the same AMB style transponders we used in this year's competitions, so the timing method should have been consistent between all three comps. During the course of the day, I had overheard that the track had been incorrectly set up at 75 yards, not 75 meters, and that had been what we ran on. This would seem to account for the statistically amazing times that were recorded that morning. thats my story and im sticking to it.

Jeez, look what happens when you try to share something. Yeah, it most likely wasn't REALLY a 3.635. But, Michigan was still faster than everyone by a large margin, and the other teams build fast cars.

I don't understand how you can say the event didn't have the fastest teams around. Sure, there were plenty of fast teams missing, but UW won East, NC State won accel at east, State won accel at West, toledo is also very fast, cincinatti was 4th at east and also good at student, Oklahoma won autox at east and more, etc.

Furthermore, the track temp was at least 95 F, which is plenty.

FYI the transponders were not used for accel, but rather photogates like at east

As it has been said earlier in this post, Who Cares?!! It sounds to me like some of you are trying to rationalize why you were slower in acceleration. The fact is you lost in acceleration by almost 0.3s or more at that competition. Learn from it and move on!

Would you like some cheese with your whine?

i can't believe no one has suggested they soaked their tires...not that i'm suggesting that. jk

Yeah man, Hot Lap's good for 2 tenths. Only works on Hoosiers, BTW...
There's a saying about a bridge that goes with this.
javascript:void(0)
Cool

And who would dare run Hoosiers at a Goodyear-sponsored event?

people who enjoy having wheel and tire assemblies that weigh the same as a 13" D2692...

Ecks, tire soaking is no joke. Ask any bandalero, legends, midget race car driver. And although I'm sure the extent of the help is dependent on the tires orginal tire compound, i can garuntee you can make goodyears stickier too. Even having some residual VHT would be an advantage.

quote:

Originally posted by Kimmo Hirvonen:
Both of these runs' times were taken with photocell system and just out of curiosity, has anyone else measured how much does it affect on time if the transponder is mounted at the rear of the car or if the time is taken with photocell system. We have done some testing with this. We put the transponder to the front of the car and then to the rear and the time difference supprised me quite a bit. We got 0.15-0.25 second differences with this so it seems that it really affects the time a lot.

Placing the transponder on the rear is the same as if you'd start that distance ahead of the light-barrier. If you think about when the system starts and stops the timing, it's fairly obvious. An optical system starts and stops the time as soon as the first bit of the car passes the sensor, while your transceiver-system starts the timing when the transceiver passes the receivers.

We've worked out that starting 1m ahead of the light barrier, chops off about 2 tenths of a second on our test-track with our optical timing system.

You have to be careful with these assumptions though. There are various ways, starting and stopping of the time can be triggered. A few examples:
Optical
* trigger when object has fully passed
* trigger when first bit of object passed
Transceivers:
* Start on first movement, stop, when you move away from both receivers
* start on change between "towards, towards" to "towards, away from", stop on change to "away, away"

In the end it holds true, that you can only compare the times of the cars under the same conditions.

For the record, our PW2.07 (the 07 car) was clocked 4.33s in Hockenheim 07, the PW06 (the 06 car) held the fastest ever recorded time in an official event of 3.86s for about half an hour, before Helsinki took first in that competition.
Since Hockenheim, we made some adujstments to the 07 car, which gained us .2s on our test-track. Let's see what we can do in Australia.

this is extremly late cause i just joined but WPI got 0-60 in under 3 sec

60 what, measured how?

Reading that post is sounds like you're proud to calculate -60 in your head that fast...

Regards, Ian

0-60 mph
and i'm not the one who calculated it.
I was just reporting data that I saw
here's the link go ahead and look
look under performance.