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Old 02-10-2006, 03:02 AM
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Batt man,
Great explanation but now you have me confused. I want to take away traction not add it. You say raise the innner pivot to lower the roll center thus giving you more roll. Don't I want to take away roll? More roll = more traction. IE: If I put on a rear Anti Sway bar I would stop roll and transfer more weight to the front tires. Correct?
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Old 02-10-2006, 03:21 AM
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Originally Posted by RC Old Man
Batt man,
Great explanation but now you have me confused. I want to take away traction not add it. You say raise the innner pivot to lower the roll center thus giving you more roll. Don't I want to take away roll? More roll = more traction. IE: If I put on a rear Anti Sway bar I would stop roll and transfer more weight to the front tires. Correct?
Sorry about taking this in another direction, but I don't like messing around too much with the geometry, once you find a decent setting you like there are easier ways to do minor balance/roll-adjustments.

Using different front/rear roll-bars is sort of a "last way out"-solution in my book. For example putting a 1.5mm swaybar in the rear and the 1.2mm in the front will result to very significant changes when driving the car. I'd think about maybe going to thicker rear oil and removing some rear droop to maintain rear consistency and balance. Though I find the EC a bit more forgiving when it comes to bad setups :-). I guess that comes of the increased chassis flex.

Note I do think you should try different RC-settings only don't go too extreme. :-). The easiest way to understand RC is basicly testing at the track!
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Old 02-10-2006, 05:45 AM
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Originally Posted by RC Old Man
Batt man,
Great explanation but now you have me confused. I want to take away traction not add it. You say raise the innner pivot to lower the roll center thus giving you more roll. Don't I want to take away roll? More roll = more traction. IE: If I put on a rear Anti Sway bar I would stop roll and transfer more weight to the front tires. Correct?

To get what you want raise the rear roll center which as the others have said reduces roll in the rear. Rear sticks less better rotation.

Rod
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Old 02-10-2006, 06:43 AM
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Ok, Im sure this has been answered before, hell, I probley asked it!! but to get the rear end to rotate more I would raise or lower the inner piviot/roll center?
Similarly, if you havent already try shortening the wheel base. I find that this is a less drastic change than changing the roll center. That way you dont have to go into the next race wondering if the change will be too much.
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Old 02-10-2006, 06:53 AM
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Originally Posted by IslandBwoy
Similarly, if you havent already try shortening the wheel base. I find that this is a less drastic change than changing the roll center. That way you dont have to go into the next race wondering if the change will be too much.
I agree with IslandBwoy here, doing small changes is a good thing.

How big is your problem RC Old Man?
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Old 02-10-2006, 08:23 AM
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Originally Posted by RC Old Man
Batt man,
Great explanation but now you have me confused. I want to take away traction not add it. You say raise the innner pivot to lower the roll center thus giving you more roll. Don't I want to take away roll? More roll = more traction. IE: If I put on a rear Anti Sway bar I would stop roll and transfer more weight to the front tires. Correct?
RC Old Man,
You are right, if you want less traction you raise the roll center, thus less roll and traction.

I read a small portion and I thought you wanted to icrease roll. My aplogy.

I did not mean to confuse anyone. However, I am sure that the explanation will help, as everyone in here issavvy enough to know what the differences in RC height do to car handling.
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Old 02-10-2006, 10:07 AM
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I think that for std. (read rubber tire) "car tuning theory" the tuning assumptions being made here usually work. However in foam tire touring it really has limited applications. Example-our foam tire touring car setups have low hinge pin locations compared to our rubber tire setups, and no sway bars (at least in the rear). In theory this should give us allot more traction because of our roll center, compared to our rubber setup. Not exactly. Why? I think it is because we are working the "other side of the curve". I believe that all adjustments on our cars work on a bell curve of some sort, and every adjustment has an optimal setting in relationship to other adjustments made on the car. Because of this sometimes the car doesn't do "what it is supposed to do" when a change is made. This is ridiculous, its a car not a two year old- it is going to do exactly what it is supposed to do according to the setup that is on the car. It has no alterative. The most important thing is to understand this, and seek answers when YOU don't understand why adjustments do what they do.
Anyways, I believe that because of the chassis roll on our foam tire cars is being controlled by the spring (primarily), (not sway bars or roll center) or cars react differently, and allow the cars weight to roll with a much smaller motion, and more progression. This allows the cassis to generate more traction at smaller chassis movements, and allows the tires to break away much earlier in the chassis roll cycle (which is beneficial to foam tire racing). The other thing that happens is that because of the length of the upper tie rod is long compared to our rubber tire setup, we get less camber gain. Because of this when the chassis rolls, we loose contact patch, and thus traction. So, I would bet that if you lengthened your rear tie rods you would get less side bite. if you softened the rear of the car, you would get less side bite. If you add more weight to the back of the car it should rotate better (pendulum effect) because of the extra roll initiated be the added weight. All of these effect the roll in relationship to contact patch of the tire. As for your question about raising the roll center blocks and traction. Nobody can tell you what this is actually going to do. They are not driving your car on your track, and it would be difficult to put your exact setup on so they could try it. The only thing is to take advice, make educated guesses, and try them to see what they do.
Now you could take all your adjustments the other direction and get similar (and possibly more predictable) results, but that is another discussion in and of it self. Good luck-Jeff
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Old 02-10-2006, 10:53 AM
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Ouch....BRAINoverload. Need to stop reading....
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Old 02-10-2006, 10:55 AM
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Originally Posted by STLNLST
Ouch....brian overload. Need to stop reading....
...I sure hope brian is Tina's nickname
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Old 02-10-2006, 10:57 AM
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Originally Posted by HarshGuy
...I sure hope brian is Tina's nickname
Playa's mess up. The over load had me going along with that voicemail you left me yesterday....LOL
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Old 02-10-2006, 11:11 AM
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Originally Posted by HarshGuy
...I sure hope brian is Tina's nickname
Hmmmm...sounds like Freudian slip to me.......Dr. Harsh, what do you think?
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Old 02-10-2006, 11:19 AM
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OK, its done. The Mi2EC Carpet editable setup sheet is done and has been uploaded to GearChart.Com. Let me know if there are any problems.

STL, you paying attention?
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Old 02-10-2006, 11:29 AM
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Originally Posted by Racer X
OK, its done. The Mi2EC Carpet editable setup sheet is done and has been uploaded to GearChart.Com. Let me know if there are any problems.

STL, you paying attention?

I'm always here....LOL It's about time.... You guys coming out this weekend? It's sure to be a blast.

Gotta serve Rob up bigtime since he's predicting me to receive a butt whippin' at this hands.
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Old 02-10-2006, 11:57 AM
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They should be coming out....the other half of that Dynamic Duo asked me to bring my "Atomic Weapon" again this week.....JIHAD! LMAO!!!

We need to get someone to post that pic.....LOL
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Old 02-10-2006, 12:24 PM
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Originally Posted by STLNLST
Playa's mess up. The over load had me going along with that voicemail you left me yesterday....LOL
LMAO ...you gotta admin, it's a good idea though
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