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Old 02-13-2008, 05:34 PM
  #25141  
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Originally Posted by seaball
math. i can make a chart, but here's the math. (don't be scared, it's about 8th grade level, maybe )

the holes for the vertical screws in our pivot blocks are 48mm apart (roughly), and that's where the 'pivot' for inboard toe is. that length is the hypotenuse. the difference in shims (f/r) is the opposite side (of a triangle). opposite over hypotenuse = sin(x). so x = invsin(shims/48). (use your calculator)

eg: 2mm/48mm = .0417. invsin(.0417) = 2.39* (approximately, 2.4*). therefore (as stated in the back of the manual). each millimeter of inboard toe is equal to 1.2* (or i think they wrote that each 0.5mm = 0.6*)

for the rear end, we reverse the blocks, so you can't just count up the front shims and divide. the reversed blocks appeared to give a 3.2mm (.125") offset (when i measured the hingepin at the front and rear). therefore arcsin (3.2/48) = 3.8*

so the unshimmed rear has 3.8* of toe per side, and every half millimeter shim used at the front blocks removes 0.6*.

that was all measured (and based on my memory from last may). maybe 'ca' can read the prints and give us some better numbers.

- yvonne durkowski -

so, guess the chart is easy, now.

shims vs. toe

0.00mm = 3.8*
0.5mm = 3.2*
1.0mm = 2.6*
1.5mm = 2.0*
2.0mm = 1.4*
2.5mm = 0.8*
3.0mm = 0.2*

now raise your hand if you just skipped to the bottom. (and we can do some extra credit at the next big race).

Chris,

Because of stuff like this, you will always be my hero.

Late

Jim
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Old 02-13-2008, 08:25 PM
  #25142  
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Originally Posted by seaball
so, guess the chart is easy, now.

shims vs. toe

0.00mm = 3.8*
0.5mm = 3.2*
1.0mm = 2.6*
1.5mm = 2.0*
2.0mm = 1.4*
2.5mm = 0.8*
3.0mm = 0.2*

now raise your hand if you just skipped to the bottom. (and we can do some extra credit at the next big race).
Raises hand...


Originally Posted by seaball
math. i can make a chart, but here's the math. (don't be scared, it's about 8th grade level, maybe )

the holes for the vertical screws in our pivot blocks are 48mm apart (roughly), and that's where the 'pivot' for inboard toe is. that length is the hypotenuse. the difference in shims (f/r) is the opposite side (of a triangle). opposite over hypotenuse = sin(x). so x = invsin(shims/48). (use your calculator)

eg: 2mm/48mm = .0417. invsin(.0417) = 2.39* (approximately, 2.4*). therefore (as stated in the back of the manual). each millimeter of inboard toe is equal to 1.2* (or i think they wrote that each 0.5mm = 0.6*)

for the rear end, we reverse the blocks, so you can't just count up the front shims and divide. the reversed blocks appeared to give a 3.2mm (.125") offset (when i measured the hingepin at the front and rear). therefore arcsin (3.2/48) = 3.8*

so the unshimmed rear has 3.8* of toe per side, and every half millimeter shim used at the front blocks removes 0.6*.

that was all measured (and based on my memory from last may). maybe 'ca' can read the prints and give us some better numbers.

- yvonne durkowski -
Hey...hey.........HEY...........you just keep your math out of my hobby!
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Old 02-13-2008, 09:08 PM
  #25143  
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Hey Chris I still don't get it?
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Old 02-13-2008, 11:25 PM
  #25144  
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have a question regarding caster adjustment..

stock caster is 4, what would be the difference if ill use 2 or 6?
the car feels good in slow tight turns but a little understeer going in and out of straight away (high speed turns). Thanks!
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Old 02-14-2008, 05:13 AM
  #25145  
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Originally Posted by Tomie
have a question regarding caster adjustment..

stock caster is 4, what would be the difference if ill use 2 or 6?
the car feels good in slow tight turns but a little understeer going in and out of straight away (high speed turns). Thanks!
more caster =more stability at high speeds
less caster=increases steering,car turns tighter and faster
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Old 02-14-2008, 07:08 AM
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Originally Posted by Darkseid
Hey...hey.........HEY...........you just keep your math out of my hobby!
lol. i know, i know. but i always feel like that the mathematical proof (if it exists) goes a long way to instilling credibility in answers. it's my skepticism kicking in. disregard, as needed.

man, have i mentioned how much i love our 'varijust' suspension (my term - lol)? seriously. having run the 2/ec forever, i still can't take for granted our infinite amount of toe options on the new ride! uh-huh
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Old 02-14-2008, 07:13 AM
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Originally Posted by seaball
lol. i know, i know. but i always feel like that the mathematical proof (if it exists) goes a long way to instilling credibility in answers. it's my skepticism kicking in. disregard, as needed.

man, have i mentioned how much i love our 'varijust' suspension (my term - lol)? seriously. having run the 2/ec forever, i still can't take for granted our infinite amount of toe options on the new ride! uh-huh
I think the way you "talk" you could be full of sh#% and we wouldn't know the difference. You at least "act" like you know what you are talking about....thus - that increases your credibility regardless if content is correct...lol
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Old 02-14-2008, 06:58 PM
  #25148  
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seaball what servo do you use in your car ?
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Old 02-15-2008, 02:18 AM
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Hey guys - i have an Mi2EC that im putting a pro setup in.
The setup comes form the back of the instruction manual. Teemu Leimu 2005
Im having trouble understanding droop. The setup sheet says that the droop is "measured form the center of the axle but i dont knoe what that means. how does the measuremetn form the cener of an axle correspond to the measurment i get of off my Hudy droop guage?
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Old 02-15-2008, 04:35 AM
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Droop is a very important tuning tool when it comes to weight transfer.
The hudy gauge is great for making sure the arms left and right are the same.
I would set your droop above ride hieght. Say your ride hieght is 5mm. Put a alan wrench under the middle of the rear/front of the chassis and raise the car. The amount of lift the chassis has before the tire come off the ground is your droop. Slide your ride hieght gauge under the chassis. That is your Droop measurement. Adjust the droop screws until both sides are close, Then use your droop gauge to make sure they are equal right to left. You can also tell because your wheels hit the board at the same time. (assuming your chassis is not tweeked) I hope I didnt confuse you
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Old 02-15-2008, 10:05 AM
  #25151  
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Originally Posted by wstuart
Hey guys - i have an Mi2EC that im putting a pro setup in.
The setup comes form the back of the instruction manual. Teemu Leimu 2005
Im having trouble understanding droop. The setup sheet says that the droop is "measured form the center of the axle but i dont knoe what that means. how does the measuremetn form the cener of an axle correspond to the measurment i get of off my Hudy droop guage?
To set droop to the middle of the axle you first have to set your camber at ride height, then take the tires off. If the measurement on the setup sheet is in the 23-28mm range then set the chassis flat on a setup board. If it's in the 33-38mm range you need to raise the car with 10mm droop spacers still on a setup board. Now take calipers and measure the distance from the board to the center of the outside edge of the axle. This is probably the most accurate way to measure droop, and it is completely seperate from setting the tweak of the car as long as your chassis is flat.
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Old 02-15-2008, 10:29 AM
  #25152  
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And as long as you never change your camber. If you decide to run a little more or less camber, your droop settings will now be off. Also your roll centers (wishbone height) will effect your measurement this way too.

I still think measuring above ride height then making sure they're equal with a droop gauge is the most consistent way to measure your droop.
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Old 02-15-2008, 11:05 AM
  #25153  
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For droop I have started doing the following

Measure the diameter of the tyre and say it equals 64mm. You dived by 2 so you have 32mm and then add 2mm; this will take you to the top of the axle. So you now have a measurement of 34mm. Take off your ride height say 5mm and the droop say 2mm from 34mm and this will give you a measurement of 27mm to the top of the axle. This way you can work out your droop easily for any tyre. I am starting to do a list so I can know what measurements to us straight away. I measure by the hex as the height is not changed by camber much.

I also then use my gauges just to make sure they are even.

Skiddins

What setup and motor you starting with at Carperwars this weekend?

Cheers

Tony
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Old 02-15-2008, 03:06 PM
  #25154  
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Originally Posted by MadBrushRacing
Skiddins

What setup and motor you starting with at Carperwars this weekend?

Cheers

Tony
Eavan 19t (MuchMore), my setup is on rcracechat in the Setups section.

Or here in the Mi3 setups section, I will be starting with the Rug Racers Spool setup;

http://www.piez0r.com/Skiddins/


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Old 02-15-2008, 04:49 PM
  #25155  
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Adam, package arrived today. Thanks for the great service.
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