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Crunch
05-12-2005, 04:17 PM
3Racing seems to be catching onto the H8 craz rather quick and they have been adding stuff to the H8 page non-stop. That I LIKE!!!!

Anyways, just saw the anti roll bars on the page and was wondering if I can get some input from you guys. What pros and cons will I get by installing these? I am running 70wt oil F/R and with -2 degrees camber F/R. I am liking this setting so far but could be improved for better and quicker steering response. Of course, I am also looking into upgrading the whole TX/RX/Servo/Speedo thing.

3Racing Front Anti Roll bar (http://www.3racing.com.hk/descriptions.jsp?prod_id=MIF-016/BU&prod_type=Options)

3Racing Rear Anti Roll Bar (http://www.3racing.com.hk/descriptions.jsp?prod_id=MIF-017/BU&prod_type=Options)

What do you guys think?
:p

chrille
05-13-2005, 10:44 AM
You will absolutley get a more stable car with those! And a little ide just, change oil to about 30 or so, 70 is way to thick for this little car! And with antiroll bars i think that even 30Wt oil would be to thick....

mpetrich
05-13-2005, 11:18 AM
Hang on, I am not totally sure that 70wt is too thick at least for the fronts. The hot setup for 18T at the indoor nationals with 70wt oil up front and 35 in the back. I guess it would be important to know what surface you are running on.
Thanks,
Matt

gustav
05-13-2005, 11:20 AM
hes running on gravel

BitHed
05-13-2005, 02:21 PM
...my 2 cents..I am a weightweenie I wont be fitting stabis at all..in fact i have cut the mount for them off the diff casings :) Hows THAT for maniacal :cool:

chrille
05-13-2005, 08:41 PM
BitHed, you ARE actually ick!:D Cut out the antirollbar holder....ok ,maybe it weights a liiiiitle, but to cut them of... Mine will be left, whatever you say! :P Cuse i will buy antirollbars, think that they will help alot actually...

adrenalinrush123998
05-14-2005, 07:24 PM
im with BH......
i just dont see my car rolling a whole lot
jeeezz.....learn to drive
ughh amatures LOL :D

i still dont see the point of a anti-rollbar

.5x8
05-15-2005, 03:30 AM
anti-rollbar is aka SWAY BAR! its for better handling u dummy bears...LOL

adrenalinrush123998
05-15-2005, 10:18 PM
i know thats it is a swaybar.....and by helping handling it also makes the car less prone to rolling over....

i still dont think its needed

.5x8
05-16-2005, 12:33 AM
okay heres the thing......take out anti roll...and then....put in sway....and then....think of better handling...and with better handling...=better performance..lol.....JUST THINK OF BETTER HANDLING! thats all that matters..lol

BitHed
05-16-2005, 01:21 AM
...ok..lets say i added JUST the front or JUST the rear...i understand the handling will be better...QUESTION: HOW will it be better? Whats going to change? And dont just tell me that it will stop rolling / swaying because I kind of have figured that out :p Spill the beans and 'sell' this to me...Make me want it...

.5x8
05-16-2005, 02:08 AM
okay..when you install it...screws hold the bar it..but the bar has to be able to move....but cannot pop out...and what it does is change the force from one side to the other...but if you tighten the screws too much...it is just like adding harder springs..so yeh..lol it will stop body lean so you get a sharper turn..O__O hope im right..if IM RIGHT! I GET FREE PARTS!! WOO lol

Hawk
05-16-2005, 03:07 AM
Read from this site, 2.7: Anti roll bars.
Bookmark this stuff because when you take the time to learn about all the vehicle dynamics, you can tune the suspension to just about anything.
Goodluck.

http://users.pandora.be/elvo/

Crunch
05-16-2005, 03:34 AM
Good stuff Hawk!!!

For all you lazy folks, here's the section about Anti Roll bars.



2.7 Anti-roll bars

Anti-roll bars are like 'sideways springs', they only work laterally. Here's how they work: if one side of the suspension is compressed, one end of the bar is lifted. The other end will also go up, pulling the other side of the suspension up also, basically giving more resistance to chassis roll. How far and how strongly the other side will be pulled up depends on the stiffness and the thickness of the bar used: a thin bar will flex a lot, so it won't pull the other side up very far, letting the chassis roll deeply into its suspension travel. Note that the bar only works when one side of the suspension is extended further than the other, like when the car is cornering. When both sides are equally far compressed, like when the car is braking, the bar has no effect. So anti-roll bars only affect the lateral balance of the car, not the longitudinal balance.

Unfortunately, anti-roll bars aren't the only things affecting the car's roll stiffness; they work in conjunction with the springs and dampers. Suppose you add an anti-roll bar at the rear of your car without changing any of the other settings. When the car enters a turn, the chassis starts to roll. Normally, the suspension on the outside of the turn would compress, and the one on the inside would extend, making for a lot more pressure on the outside tire. With the anti-roll bar however, the suspension on the inside will be compressed, so the chassis will roll less, and the rear of the car will sit lower than normal. So the rear has more weight on it, and it's distributed more evenly over the two tires. This makes for a little more, and more consistent traction. Remember that this is in the beginning of the turn, the situation is different in the middle of the turn. Normally, without the anti-roll bar, the chassis would stop rolling when the roll torque is fully absorbed by the outsid e spring. But with the anti-roll bar, some of that torque is absorbed by the anti-roll bar, and used to compress the inside suspension. So the outside suspension won't be compressed as much as it normally would, making the rear of the chassis sit up higher than normal, so less weight is on the rear of the car, and more at on the front. It's as if suddenly the rear has become stiffer, making for more steering and a little less rear traction. Rear traction is more consistent however, because the weight is distributed more evenly over the rear tires, unless the track is really bumpy, that is; anti-roll bars can really mess up a car's rough track handling, so they're rarely used on bumpy tracks. Adding an anti-roll bar at the front of the car has a similar, but opposite effect: it decreases steering, but makes it much smoother and more consistent. It can stop the front from 'biting into' the surface too much, making the turning radius big and smooth. This can come in handy on large, wide tracks.

Math-wise, the torsion stiffness of the middle part of the bar goes up with the fourth power of the bar's diameter, and for the two side parts, torsion stiffness goes up with the square of the diameter. Keep this in mind while changing anti-roll bars.


I run on a tight track with tight turns, so I guess I'll be trying the rear anti roll bar......

BitHed
05-16-2005, 04:20 AM
..that pandors site is like the RC bible :cool:

Joan
05-16-2005, 03:28 PM
The best explanation ive ever seen.... these guys knows about it :cool:

Hawk
05-16-2005, 03:48 PM
My best luck is to start with the out of the box setup, usually pretty neutral, then tune to the track. Setup ride height, shock dampening then look at turn in and last is flight. Once you get the tires to stay on the ground for most of the flat parts (there is a contradiction in terms) and make sure the landings are handled well. Can't control a car that is bouncing and flipping on the big jumps. Next look at the turns. Look for balance, left and right, then try to get the dynamics of the turns working. turn in is important and driving style has a lot to do with exactly how much grip you want on the front and rear. If you can drive it around the track (not pushing the front tires nor swinging out the rear end) then you can use the throttle and breaks to cause those things to happen on command.
Last is the balance you get out of the anti-roll bars. Usually you do tiny changes in anti-roll bars. Less is more most of the time. If it is wet, less bar front, more in the rear. toward the middle of the day when track dries out, a little less bar in the rear and a little more in the front. Back to more neutral setting. At the end of the day, when the track is rutted and hard, maybe back out both bars to get a little more lively suspension on the corners and bumpy fast parts of the track.
When I say more bar, you move the collar in or out on the bar, making the lever on the torsion part that is perpendicular to the chassis center line. The farther out toward the end of the bar, more leverage. This also requires a little more travel to get a response so it is a very fine setting. Play with it some if you are bored and have the time. 1/8 setup sheets talk about the distance the collar is from the end of the bar as the setting on this device.

Any suggestions or comments welcome. :D

pimpsmurf
11-04-2005, 12:03 AM
HAWK! Seriously man! Thank you! Very informative. This thread needs some votes! Now does anyone know which colors are hard and soft? hehe

-JNY

plain_simple
11-04-2005, 04:53 PM
usually hard or softer depends on the thickness of each sway bars... the thicker the hardest...
On the one above i'm sure but i also think that it can depend in which material the sway bars are done.. usually stainless steel is harder then aluminium, etc.. i think... isnt it?! :confused:

pimpsmurf
11-04-2005, 05:32 PM
I don't know what type of material the 3racing ones are because they are painted, but the yellow is thicker, and it harder. The green and red seem to be the same size, but the red is softer. I'm going to try to strip the paint off cause I want to use the green one in the rear with the red up front, and they clash something nasty with all this nice blue alloy!

-JNY

plain_simple
11-04-2005, 06:51 PM
If you do want to get the paint out try buying some diluent and submerge them on it, then you should easily get the paint out...

Hot tip: Dont forget to find some sort of code to mark each one of them so you can know what is what, trust me when i say that sometimes things get confused ;)

pimpsmurf
11-04-2005, 06:58 PM
What do you mean by diluent? I'm not trying to dilute it! =)

I'm worried that paint remover will harm the metal. I'll have to check around and see. I might end up just sanding and polishing them. *shrug*

Actually, the 3 racing ones are easy to tell appart outside of the colors unless they get weakened over-time. The red one is much easier to bend than the green.

I'll probably only remove the colors from the 2 I want to use to save some time, so it would be impossible to mix them up.

-JNY

mat3833
11-05-2005, 10:45 PM
i love that website!! it is on my favorites. that place is like... well the bible as bit said. i think i will get a set of rear once i get my other stuff taken care of.

Matt

pimpsmurf
11-06-2005, 02:55 AM
I've only been running on asphalt so far, with the front and rear hard bars on. When you turn it oversteers for just a second, then understeers like mad. I can't wait to get it on my track and try out all the different setups. I'll have to ask some of the 1:8 buggy drivers what they use. :)

-JNY