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Old 11-17-2009, 11:05 AM
  #8101  
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what problems are there in mod except breaking of flexplates after hitting the walls? Just curious.
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Old 11-17-2009, 11:22 AM
  #8102  
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My problem with mod is getting enough steering without making the car way too twitchy and/or having a snap loose problem.
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Old 11-17-2009, 11:31 AM
  #8103  
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Originally Posted by V12
what does that mean? I just noticed there are new flexplates coming.
It should help the pod to return to center position better. I've always had to work with the steering wheel to get the car going straight, it's not a problem with a slower motor, but with modified it's sometimes quite tricky.
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Old 11-17-2009, 11:36 AM
  #8104  
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Will the RR upgrade kits (particularly the lipo chassis version) be updated to include the new carbon flew plates as a running change? I'm looking to update my db12r to db12rr specs and use the lipo chassis, but I'm also wanting to update to the carbon flex plates as I've snapped a few fiberlgass ones myself.
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Old 11-17-2009, 11:39 AM
  #8105  
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Originally Posted by gubbs3
My problem with mod is getting enough steering without making the car way too twitchy and/or having a snap loose problem.
Do you get that feeling that it's too twitchy in the corner entry, but in the same time it still understers on corner exit..? If so then try a harder center spring, it will transfer more weight to back when you when you are deaccelerating thus you will gain more rear traction and reduce the twitchiness and put more weight to the front when accelerating going out of the corner. This usually helps me.
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Old 11-17-2009, 12:07 PM
  #8106  
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Technically it isn't transferring weight to the rear but transferring less to the front.
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Old 11-17-2009, 01:27 PM
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I'll give the harder center spring a try this weekend. Last race I did find that heavier oil in the center shock did make the car feel more planted off power so the harder spring might give it back the on power steering I need.
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Old 11-17-2009, 06:31 PM
  #8108  
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Guys...I need a little help. I was running pretty good this past weekend at my local track. I qualified 5 out of around 12. I should have done a-lot better however my car kept looping out on me to the left side really bad. The funny thing was that it didn't happen until around the 3 min mark. I had plenty of traction until that mark and till the end of the race. I actually was in 3rd place until this point and then the grip went away.

Any suggestions?

Running Jason's standard setup with magenta tires all the way around.
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Old 11-17-2009, 07:21 PM
  #8109  
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does anyone have pictures of there bmi t bar cars? If so it would be a great help to post them..
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Old 11-17-2009, 08:16 PM
  #8110  
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Originally Posted by SwampDog32
Guys...I need a little help. I was running pretty good this past weekend at my local track. I qualified 5 out of around 12. I should have done a-lot better however my car kept looping out on me to the left side really bad. The funny thing was that it didn't happen until around the 3 min mark. I had plenty of traction until that mark and till the end of the race. I actually was in 3rd place until this point and then the grip went away.

Any suggestions?

Running Jason's standard setup with magenta tires all the way around.
Usually when the car loses rear bite after a few minutes or later into the race its because the car is set up too loose from the start and overworks the rear tires. Dial out some front end grip to start and see the difference.

As for spinning only in one direction just go back to the basics of finding a tweak. Check tire size, left/right balance, front springs, bent/stressed/broken parts, etc.
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Old 11-17-2009, 10:43 PM
  #8111  
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Originally Posted by Tulsa TC3
does anyone have pictures of there bmi t bar cars? If so it would be a great help to post them..
They aren't t-bar cars any longer. They are a link style car but use a flexible link rather than a link and a spring. There are several pics on BMI's site at www.bmiracing.com
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Old 11-18-2009, 07:57 AM
  #8112  
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Originally Posted by SwampDog32
Guys...I need a little help. I was running pretty good this past weekend at my local track. I qualified 5 out of around 12. I should have done a-lot better however my car kept looping out on me to the left side really bad. The funny thing was that it didn't happen until around the 3 min mark. I had plenty of traction until that mark and till the end of the race. I actually was in 3rd place until this point and then the grip went away.

Any suggestions?

Running Jason's standard setup with magenta tires all the way around.
If your running carpet, try going to a synthetic rear tire and a slightly harder front like a 2x pink or a lilac. The front tires are gumming up and making that happen.
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Old 11-18-2009, 08:29 AM
  #8113  
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Originally Posted by gubbs3
Usually when the car loses rear bite after a few minutes or later into the race its because the car is set up too loose from the start and overworks the rear tires. Dial out some front end grip to start and see the difference.

As for spinning only in one direction just go back to the basics of finding a tweak. Check tire size, left/right balance, front springs, bent/stressed/broken parts, etc.

So on that topic... how do you set tweak on these cars? The set screws on the flex plates are not true tweak screws.

I know the car shouldnt tweak itself as far as suspension is concerned, but tweak is also to corner ballance the car to equally distribute weight to all corners. My car does have some ballance issues that could be remedied with some simple tweak changes.

I know a few pages ago we talked about shimming the pivot ball on the aft part of the flex plate, but there seemed to be some concern that it would throw off the geometry or something.

Thoughts, ideas, comments?
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Old 11-18-2009, 11:39 AM
  #8114  
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Originally Posted by Clegg
So on that topic... how do you set tweak on these cars? The set screws on the flex plates are not true tweak screws.

I know the car shouldnt tweak itself as far as suspension is concerned, but tweak is also to corner ballance the car to equally distribute weight to all corners. My car does have some ballance issues that could be remedied with some simple tweak changes.

I know a few pages ago we talked about shimming the pivot ball on the aft part of the flex plate, but there seemed to be some concern that it would throw off the geometry or something.

Thoughts, ideas, comments?
Simple answer - I don't! Build the car correctly, balance the electrics on the main chassis and it always comes up roses on the coin test / tweak station.

Despite extensive crash testing (!) there has never been a tweak in the car that could not be explained by some damage somewhere - and that is very rare. No, I don't know why, it just works! All the guys racing BMI at our Nationals have the same experience. HTH
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Old 11-18-2009, 01:42 PM
  #8115  
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Originally Posted by Clegg
So on that topic... how do you set tweak on these cars? The set screws on the flex plates are not true tweak screws.

I know the car shouldnt tweak itself as far as suspension is concerned, but tweak is also to corner ballance the car to equally distribute weight to all corners. My car does have some ballance issues that could be remedied with some simple tweak changes.

I know a few pages ago we talked about shimming the pivot ball on the aft part of the flex plate, but there seemed to be some concern that it would throw off the geometry or something.

Thoughts, ideas, comments?
Actually, when you have the tweak screws touching the chassis, you will tweak the car the same as any other. It is best to balance the car and not rely on tweaking. This goes for any car. You do not want to preload 1 spring more than the other in any case. On link cars with side springs, you either run no preload on the springs or even preload from left to right. Try your best to balance the car and you should be fine.
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