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Old 05-30-2012, 03:50 PM   #136
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So reduce the spacing on the roll center adjuster?
Yeah. Remove your 3 mm spacer and give it a run. you may add back a mm but it you pull it all out you should see a big difference and you can work your way back.
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Old 05-30-2012, 04:10 PM   #137
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Yeah. Remove your 3 mm spacer and give it a run. you may add back a mm but it you pull it all out you should see a big difference and you can work your way back.
So additional spacers increase traction roll? I thought it was to reduce it...
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Old 05-30-2012, 04:42 PM   #138
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So additional spacers increase traction roll? I thought it was to reduce it...
By adding spaces under the inner camber link you are lowering the roll center and encouraging the chassis to roll more. If the roll center is too low then the chassis rolls over. The amount of droop in your suspension arms will increase or decrease the effect. Set your droop to 1mm and raise the roll center by pulling the spacers. You will be demanding more mechanical traction from your tires but the chassis won't roll as much and it should quit rolling over in the turns. If the roll center gets too high by causing the car to severely push then try adding 1mm back under the inner camber link. Its all a balance between droop roll center and suspension set up. Correct the traction rolling then you can adjust the suspension properly. You can also use roll center to increase or decrease tire temps because of the mechanical traction changes in the tire. Roll center is very misunderstood. A lot of people just set it as low as they can and go with it. If you can find the proper roll center for the car and the racing surface you can really dial in the rest of your suspension and have a car that is glued to the track.
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Old 05-30-2012, 04:59 PM   #139
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By adding spaces under the inner camber link you are lowering the roll center and encouraging the chassis to roll more. If the roll center is too low then the chassis rolls over. The amount of droop in your suspension arms will increase or decrease the effect. Set your droop to 1mm and raise the roll center by pulling the spacers. You will be demanding more mechanical traction from your tires but the chassis won't roll as much and it should quit rolling over in the turns. If the roll center gets too high by causing the car to severely push then try adding 1mm back under the inner camber link. Its all a balance between droop roll center and suspension set up. Correct the traction rolling then you can adjust the suspension properly. You can also use roll center to increase or decrease tire temps because of the mechanical traction changes in the tire. Roll center is very misunderstood. A lot of people just set it as low as they can and go with it. If you can find the proper roll center for the car and the racing surface you can really dial in the rest of your suspension and have a car that is glued to the track.
I have tried everything, except that. you sir, are a genius!
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Old 05-30-2012, 10:09 PM   #140
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I have tried everything, except that. you sir, are a genius!
Well thank you but I'm only passing information along that I have learned. I like to study and read about tuning these cars and I love to adjust and wrench on them. Most importantly I did and still do a lot of exactly what you did. I ask a lot of questions. I'm glad I could help out. Please, if you have any other questions just send me a pm and I will do my best to answer and help as much as I can.
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Old 05-30-2012, 11:27 PM   #141
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Interesting that this topic is current again

My VTA car has done pretty good actually as I have been getting back into racing again. For the most part, it has been slightly loose, but not bad at all. Tonight, during the 1st half of qualifying, it was handling very well, but again, just a tiny bit loose on the rear. I laid the rear shocks down one hole from center (Xray T3) and went back onto the track and it did very well. During the Main, I had 3 times where I traction rolled in the same tight, fast corner. I am sure the track's traction came up during the night but it's amazing how this one small change made a pretty significant difference.

I'm going to leave the car alone and run it as is for qualifying next week. If it feels like traction is coming back up again like tonight, I'm going to stand the shocks back up.
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Old 06-02-2012, 03:15 PM   #142
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how much do tire inserts play a role in traction rolling? I have medium inserts, but wouldnt softer inserts add traction increasing the roll?
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Old 06-02-2012, 04:12 PM   #143
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how much do tire inserts play a role in traction rolling? I have medium inserts, but wouldnt softer inserts add traction increasing the roll?
Going softer can increase the tendency to roll over because the softer setup will increase traction.

Have you had a chance to test your changes?
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Old 06-02-2012, 04:37 PM   #144
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I've done a lot of reading through this thread the last few months when I was having traction rolling problems and came to the conclusion that many of the general thoughts on the topic are very... well, general. Soft springs alone won't cut it from what I've experienced. It's great for lessening the tendency for the inner suspension to push the chassis over but on the outside it hinders the ability for the suspention to keep the chassis down. Soft springs and stiffer sway bars worked for me. I found that my car was rolling in the center of the corner over the rear. I was already on very soft springs but once I upped the sway bar considerably the rolling tendency was completely gone. Now obviously this will create a negative effect in one way or another and for me it was loose entry off throttle (not surprising), but I found other way to fix that whilt keeping the stiffer rear sway. This was 17.5 TC.
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Old 06-02-2012, 05:02 PM   #145
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Going softer can increase the tendency to roll over because the softer setup will increase traction.

Have you had a chance to test your changes?
Not yet. Not for atleast another week. I got my hands on a protoform body instead of the tamiya Nsx( steering on Nsx is insane) I also went to 1.5 mm spacers and I will see how that works, possibly no spacer, but I want to test first. I also removed the ifs for more consistent handling.
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Old 06-02-2012, 05:39 PM   #146
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I've done a lot of reading through this thread the last few months when I was having traction rolling problems and came to the conclusion that many of the general thoughts on the topic are very... well, general. Soft springs alone won't cut it from what I've experienced. It's great for lessening the tendency for the inner suspension to push the chassis over but on the outside it hinders the ability for the suspention to keep the chassis down. Soft springs and stiffer sway bars worked for me. I found that my car was rolling in the center of the corner over the rear. I was already on very soft springs but once I upped the sway bar considerably the rolling tendency was completely gone. Now obviously this will create a negative effect in one way or another and for me it was loose entry off throttle (not surprising), but I found other way to fix that whilt keeping the stiffer rear sway. This was 17.5 TC.
You are correct. There is a lot of general information on traction rolling. There are many reasons for traction rolling and you could do hours of reading an still not find your answers. I have found that most traction rolling can be cured with roll center adjustments but you need to re tune the chassis to work with the new roll centers. Once the correct roll center is found your car will hook up much nicer.
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Old 06-02-2012, 10:56 PM   #147
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Lowering the roll centers cured it for me, but I have also found that excessive tire wobble can also cause traction rolling, and your rear to kickout.....Once these too are within spec, you can move on to slightly softer setup, but never stiffer...
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Old 06-04-2012, 02:40 PM   #148
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Lowering the roll centers cured it for me, but I have also found that excessive tire wobble can also cause traction rolling, and your rear to kickout.....Once these too are within spec, you can move on to slightly softer setup, but never stiffer...
Hmmmm my experiences were different. Once I raised the roll center it quit rolling over. I can also run soft or stiff depending on track conditions. It must revolve around why the car is rolling over in the first place.
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Old 06-04-2012, 02:46 PM   #149
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Hmmmm my experiences were different. Once I raised the roll center it quit rolling over. I can also run soft or stiff depending on track conditions. It must revolve around why the car is rolling over in the first place.
Now dangit! How many times do I have to tell you. You will never go fast until to learn how to slow down! So what's the latest? Send me a pm, I got something for you.
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Old 06-04-2012, 03:21 PM   #150
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Now dangit! How many times do I have to tell you. You will never go fast until to learn how to slow down! So what's the latest? Send me a pm, I got something for you.
Lol. you're right there. I have a good handle on how hard I can push the usgt car without over driving but the f1 has so much traction it is really easy to over drive. I feel like I'm on a lazy Sunday drive when I'm turning my fastest laps. The discipline is really tough to learn.

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