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rensuchan
2011.02.01, 05:34 PM
I tried doing a search and couldn't really find anything easily so I figured I'd just open a thread about it.

Say your track layout has a quick left to right chicane section. What are some general tips to get your car to transfer direction quicker? Is there something with springs or spring cups that can help? Do I need to stiffen the rear so that it doesn't bite as much? I feel like I could pick up a little bit of time in those sections if I could get around them a little faster.

Deca
2011.02.01, 06:07 PM
A bit of camber in the front should help, and maybe stiffer rear springs. Also softer fronts, but you have to figure out if picking up that speed in the low speed section is worth making your car harder to control in the faster parts of the track.

Honestly just some camber in theory should be what you're looking for (1.5 degrees might be a good starting point, I still don't really know how MR03s adjust camber) and shouldn't screw up your setup around the rest of the track.

Digitalis West
2011.02.01, 07:04 PM
The biggest thing I do is make sure the suspension is super smooth. You still need damping (usually from grease or oil) but there should not be any friction in the suspension. Friction causes the suspension to "take a set" through a corner which helps stability in bumpy straights and sweepers but hurts fast transitions.

In front use an upside down kingpin or double-a arm setup with some grease on the lower knuckle or spring cup for damping. In back make sure that the damper disks, damper plates and damper post are mirror polish smooth with no play between the disks and post and oil for damping. You can also use the trishock setup in back but it can be more tricky to setup.

You will have to play around with spring and damping rates depending on your setup. Once you have the balance of the car where you want it with the spring rates, start trying different things with the damping. Too little damping and the car will be unstable in bumpy straights, sweepers and tend to hop or traction roll. Too much damping and the car will have slow corner entry and poor transitions in the chicane.

It will take some work to get it right... but trying things out and playing around with the car is half the reason I got one.

rensuchan
2011.02.01, 08:17 PM
Btw, I'm on MR-02, you know this Deca =P

Already using 1.5 degree camber but I do have access to 2 degree knuckles as well. I could give that a shot.

I've also been told it could just be slow transmitter response. I'm not using any expensive transmitter (Airtronics MX-A) and I'm still on AM, could that be the issue?

color01
2011.02.01, 09:31 PM
That would do it, yes -- but you can still improve the response of the MR02 front end.

By a "bit" of camber, I would take that to mean less than 1.5deg; for fast transitions, you're not going to be letting the car roll to its full extent (that it would in steady-state cornering), so you will get faster steering response by using LESS camber. Probably not 0, but I've used 0.5 with good results before. If you needed every last bit of the 1.5deg camber for the rest of the track though (have you checked your front tire wear?) then I would suggest NOT sacrificing the rest of the track for this one chicane.

Stiffer front springs will actually increase turn-in response, and will help you turn into the chicane more quickly. Again, this will come at a sacrifice of steady-state cornering ability, so you may have to use softer front tires to compensate for the stiffer springs.

Are you using wide-offset front wheels? The MR02 servo is fast, but not THAT fast, so wide-offset front wheels will slow down the overall steering response. 1N is the max offset most people run on the MR02 front end. One of the most popular setups from back in the MR02 heyday was the Reflex WTF or WTF2 coupled with 0N or -1N front wheels. Excellent mid-corner stability and quicker turn-in response.

I normally don't advocate buying parts to fix a setup, but in your case, a tri-shock setup of any brand will make the car significantly faster through chicanes. The side springs really help to recenter the rear pod faster than a T-plate alone can, so you transfer the weight off one side faster, i.e. faster response and getting around the second corner faster.

Deca
2011.02.01, 09:44 PM
Btw, I'm on MR-02, you know this Deca =P

Already using 1.5 degree camber but I do have access to 2 degree knuckles as well. I could give that a shot.

I've also been told it could just be slow transmitter response. I'm not using any expensive transmitter (Airtronics MX-A) and I'm still on AM, could that be the issue?

Oh yeah, my bad ^^;

herman
2011.02.01, 10:47 PM
hmm... interesting...

wondering if anybody can put up videos of the front and rear tire & suspension while the chassis is running...

something like this video (http://www.youtube.com/watch?v=o1o-TvZQdek)

probably compare mr01/015/02 front suspensions?

unfortunately though the weight of the vid cam on the chassis would probably affect the performance/set up...

nevertheless it would give us some sort of idea what the suspension is doing...

on a much smaller scale... :D

rensuchan
2011.02.02, 12:50 AM
By "that would do it," did you mean the transmitter?

By a "bit" of camber, I would take that to mean less than 1.5deg; for fast transitions, you're not going to be letting the car roll to its full extent (that it would in steady-state cornering), so you will get faster steering response by using LESS camber. Probably not 0, but I've used 0.5 with good results before. If you needed every last bit of the 1.5deg camber for the rest of the track though (have you checked your front tire wear?) then I would suggest NOT sacrificing the rest of the track for this one chicane.

The Ann Arbor track actually changes layout, we kind of set up whatever we feel like when we meet so it's generally never the same... but whenever we have a slower section with quick lefts and rights (also the smaller HFAY layouts) my car doesn't seem to change direction as fast as some of the others. I generally don't have trouble with the faster sections of the track.

I have access to a 1 degree camber knuckle as well so it would be little bit less than the 1.5. I'm also running the PN Green springs on the front so I have a few harder options there too.

Are you using wide-offset front wheels?

Murcielago body with +3W rear 0N front.

I normally don't advocate buying parts to fix a setup, but in your case, a tri-shock setup of any brand will make the car significantly faster through chicanes. The side springs really help to recenter the rear pod faster than a T-plate alone can, so you transfer the weight off one side faster, i.e. faster response and getting around the second corner faster.

If not using a tri-shock would you recommend trying a stiffer t-plate?

I'm wondering if I just need a slightly more "grippy" front tire. Currently I'm using the Kyosho 30D front slicks, would a 30D radial give a small bit more grip?

color01
2011.02.02, 01:44 AM
Kyosho 30 front slicks are fine, the radials will only give you a little more grip overall and of course they wear down after a few sessions. I would try PN front tires if you have the time, the carcass of the tire is stiffer so you automatically get a little faster response there, and there are many compounds to choose from to really fine-tune the response. I would probably start with PN 20 slicks, scrub off the top coating with a tire truer, and then see how they perform.

And yes, AM cars are significantly less responsive than their ASF counterparts. This doesn't make a huge difference in terms of absolute lap times (just anticipate inputs like they did "back in the day") but if you're wondering where the laggy feeling comes from, AM radio is a suspect.

geeunit1014
2011.02.02, 11:34 AM
A stiffer t-plate will definitely make the car transition faster. Trying to put more front grip in the car (tires or camber) may not give you the result you want, it will definitely make the car more aggresive, but not really better in transitions. Making the car transition better isnt really about tires, assuming the tires are in the ballpark, but roll centers and springs. Stiffer springs are more responsive than softer ones, and higher roll centers react quicker than lower ones. Since you cant really adjust the roll center too much on a mini z, the next best option is springs. The t plate is essentially the main spring for the rear end, and going stiffer there will definitely make the car transition faster.

Deca
2011.02.02, 11:49 AM
Is it possible to lower MRs without the H/T plate having issues hitting the ground? I'm sure you couldn't lower it too mich but on a car this small it migh make a noticeable difference in response.

Pure speculation, pay me no mind lol