OK, good example. And in SCCA the transponder can be anywhere you want but I have yet to see anyone attach it to the back of their car. Fooshe's example is the first I've ever heard of.

 

Placement doesn't matter for time trials either ... which is what my experience is in so ...

 

This wasn't an SCCA event, but even if it was, John is right and you can place it anywhere you want.

I learned later that in this case, the guy had a new crew member handle the transponder re-installation after a repair job to the front end of the car. He never even thought about having to tell him where to locate the unit. Oddly enough, this was the third time I had heard of this happening. That is why I asked the question "where is your timing device on the car" to him. He looked up front and it was not there (obviously), he then called the guy and who put it back on the car and when he told him where he put it, the guy's face just went beat red.

It was a rookie mistake and a reminder that not everyone thinks of everything.

 

Correct, that is all about your personal time and not door to door stuff. In fact, If you have a choice I would rather have it in the rear for a time trial.......wouldn't you?

Ok, now....you've seen my M.O., think about it.....

 

I would have it on a threaded rod that ran the length of the car (underneath) with a little drive motor. It would be in the rear of the car when I started the fast lap and then in the front of the car at the end of the fast lap.

 

If it had been an SCCA then the transponder placement wouldn't have mattered as the GCR requires a visual determination of the winner and not a reliance on the transponders.

Did the results you mention stand? I'd hate be on the short end of a decision that artificially changes the result of a race based upon a timing system placement.

As for why you would want the transponder at the rear of a car for time trials, my guess would be that you are lengthening your acceleration down the s/f straight by the length of your car. If you are trying to pull every thousandth of time, I can see that make a difference. Measureable or not, I couldn't guess.

 

Without thinking about it too much, it doesn't matter where it's placed... you're either "gaining" time at the beginning of the lap, or at the end of the lap... depending on if it's placed in the front or rear.

 

Not sure about the extra weight of all that, but I like your thinking John!

 

I did not know that about the SCCA events. And the results were made official, so it did stick. In a measure of good sportsmanship, we all traded trophies.

As for your answer to the statement.....you are right on. Under acceleration, the car is going faster the further is travels. As we all know, for that type of event, you want to be hitting your maximum speed at the start so your time may be as low as possible. And yes, it is probably a measurement in the 100's or 1000's, but sometimes that is what is comes down to.

 

when we bought our race car, it was often raced in the SE division of SCCA. The transponder, when we got the car, was placed about equal to the rear wheels. We moved it to the front of the car.

 

Amatures...

I am building an air cannon that will shoot my wireless transponder at over 300 MPH out the front on the final lap.

 

you get out of that Miata you wouldn't need an air cannon

 

I'm trying....I'M TRYING!!!

 

It'll just bounce off the back end of all the other cars in front of you and skip into the infield, having never crossed the finish line...

 

I plan to aim it high since I will have shoot it over the entire field.

 

I the cannon fails, you could always go to plan B. Tape it to your front bumper with two sided tape on the open side. Get behind the leader on track and bump draft him or go a bit hot into a turn behind him. When you hit is rear bumper, the transponder will stick to his car. It's not a win, but at least you're on the podium.

 

LOL. I have thought about switching with a GT1 Friend of mine to throw him and everyone else for a loop during Practice Laps.

 

LMAO Drinking on the job again Marty?!

 

OK, here's what a team actually did during a SCCA qualifying session at Sears Point. One of their crew member had the transponder in his pocket and he would walk across the start/finish loop in the hot pits at the appropriate times. They got caught when the crew member forgot and walked across the loop to talk with another crew member and someone in T&S saw the timing trip on the computers.

 

Lol
new phone
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