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Post by boh2112 on Jan 30, 2006 13:21:18 GMT -6
Hello to All,
I am a 1st time poster and have to say that I have learned alot reading this forum. A couple of months ago I had never even seen a pinewood derby car. With the tips I got off of this forum my son and I built a car that won his den (Tiger Cub) and placed 3rd in the pack out of about 85 cars. We have qualified for district. You guys definately know what you are talking about! Thanks!
Now for my question. When my car hits the flats it starts fishtailing but it dose'nt seem to effect the performance to much. What causes this? Should I attempt correct this or should I leave it alone since the car seems to be so competative?
For a very close representation of what is happening to my car please refer to the Jan 2006 WIRL racing video - Modified division. I believe the name of the car is "Geppard". "Geppard" seems to have alot of success with the fishtailing action as my car does.
Once again thanks.
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Post by Smokinjoesracing on Jan 30, 2006 18:58:18 GMT -6
You probably have a stability problem due to one of two things. If your CG is less than 7/8ths then it's probably weighted too much in the rear. Also try realignment on the rear wheels. I hope this helps because a car than races straight...races faster.
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Post by SpeedGeek on Jan 30, 2006 19:53:56 GMT -6
The instability is due to the CG being far back. When the car is on the incline, it is stable because more of the weight is shifted to the front wheels. When the car hits the flat, the weight on the front wheels is reduced and it goes unstable.
I did the same thing to one of my cars last year, but with much less success due to other factors that are too painful to discuss.
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Post by Panzer on Jan 30, 2006 20:21:47 GMT -6
If we had any idea Gepard was going to fishtail as bad as it did on the WIRL track it never would have been sent to begin with. No doubt its times would have been better if it had taken a more direct path down the track.
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Post by slkrnsntracing on Jan 30, 2006 20:36:07 GMT -6
No doubt its times would have been better if it had taken a more direct path down the track. Panzer, That's the scary part. We'll probably find out how much difference it makes next month. Good luck. Phil |
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Post by Mood Swing Productions on Jan 30, 2006 20:46:29 GMT -6
unless your name is panzer.. refers to january race
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Post by boh2112 on Jan 31, 2006 8:13:22 GMT -6
Thank you guys very much for responding. I will try and implement your suggestions and hopefully have a good showing at district.
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Post by patmanruls on Jan 31, 2006 9:18:00 GMT -6
No doubt its times would have been better if it had taken a more direct path down the track. Yup, that's the scary part... or if it had been a circle track, we'd have gotten beat too....  |
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Post by woodenwonder on Jan 31, 2006 10:06:13 GMT -6
What did they say on Days of Thunder? "Loose is fast"
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Post by Mood Swing Productions on Jan 31, 2006 20:38:32 GMT -6
the first car i ever built my son won best in show but could barely make it down the track. it was 4 years ago and my son speaks of it as if it happened as i type this. we totally forgot to weight the car. but hey it looked good. ha so when we got there we had to apply a boat load of quarters hot glued to it. like 3.50$ worth. if we didnt run the car backwards it would jump the track. in one race it was in lane 5 of 6. jumped out to the lead on the start. jumped the track and took out 3 cars. and yes we got it on video hahahaha
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Post by slkrnsntracing on Feb 1, 2006 19:53:16 GMT -6
Now....nobody tell him it might slow the car down some and we can all pick up a place this month; heheh Your secret's safe with me. Phil |
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Post by Panzer on Feb 1, 2006 21:19:29 GMT -6
What a great bunch of guys, always there with advise when you need it.
Warthog, I know you mean well?
But first let me check out the last videos to see how that alignment technique performs on your cars.
Unfortunately, due work commitments, it doesn't look like we will be making the February WIRL race. Gepard needs some serious work before it can show its face again down in Georgia. Look for it again maybe in March together with a teammate. In the meantime best of luck to everyone.
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Post by woodenwonder on Feb 2, 2006 10:53:52 GMT -6
Hey Panzer you can send Gepard to me. I would be happy to disassemble it for you to see why it was rattling. Then I will send it in and even pay your entry fee.  |
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Post by WarpSpeedINC on Feb 2, 2006 11:20:10 GMT -6
Should we start the bidding!! ;D
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Post by woodenwonder on Feb 2, 2006 13:01:01 GMT -6
Should we start the bidding!! ;D I offered first, you guys stayout of it! ;D |
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Post by slkrnsntracing on Feb 2, 2006 13:29:18 GMT -6
I'll start at $20.00 and throw in a couple cars that should be very competitive in the April Fools Race.
Phil
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Post by Mood Swing Productions on Feb 2, 2006 17:41:00 GMT -6
hey panzer. unlike your other friends here i do not wish to cheapen our friendship
by making things about money. youd feel cheap and sleezy about it and i dont
want you to feel that way. you can send me the car, i wont lessen our relationship
to money transfering
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Post by cheelwheels on Mar 11, 2006 18:40:52 GMT -6
HELP! HELP! HELP! Car is fish tailing bad. race is thursday. What canI do? Car took 3rd last Sunday in adult division at district race and ran smoothly on analluminum track. Pack race thursday on a masonite homebuilt. We test ran it today and Wow was it bad.
ANY THOUGHTS?
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Post by boh2112 on Apr 24, 2006 4:25:47 GMT -6
We had our district race this week end. I thought I would give an update on my Tiger's car performance. Per this thread's advise I moved some of the weight forward to enhance stability but not very much as I was just to paranoid about loosing to much speed on the slope. The results were that the fishtailing seemed to calm down a bit but it was still there. There were about 150 cars in the race. Our car placed a very close second in the Tiger Cub division of 31 cars (we had the fastest individual run of the day) and was third overall fastest qualifier going into the finals. In the finals the car really dropped off in performance and finished 12th. The car that beat us in Tiger Cub Division won the overall.
This being our first experience we are very happy with the results (trust me when I say that I did not even think we would be competative in the Tiger Division of our own pack) and very greatful for all of the tips offered on this forum. However, it is bugging me how our car ran so differently in the finals. We were not allowed to relube or tinker with the car before the finals, it did not seem to have any violent crashes and it was not dropped by any of the personnel working the event. I know there could be a thousand reasons but would anybody care to venture a guess as to the drop off in speed? If there are any facts or circumstances that you need to know just ask and I will do my best to answer. It would nice to have this problem addressed for next year.
Thanks!
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Post by Buckeye on Apr 24, 2006 10:10:09 GMT -6
I know the tendency is to adjust the back wheels, but sometimes a slight realignment of the dominant front wheel can fix the rear end wobble.
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