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Old 09-10-2009, 08:35 PM
  #1527  
PartTime
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Ok, my car was dialed. So dialed that pretty much everybody that saw the car told me it looked awsome and not to touch it. That was the setup posted on rc10.com. Well, I raced the car two more races like that. The next race I couldn't unscrew my head from my butt so the finish was not that great. The last race I had my head screwed on right and did very well with the car again. It was the same easy to drive missile for all three races. The following race it started to develop a double steer. Then it started to throw the rear into the corners. I rebuilt everything. I cleaned everything. I realigned...you get the idea.

Well that chain of events sent me off on a tuning spree. I played with just about everything I could over the last couple weeks of track time. First off i would like to say that the car could be a step or two off on chassis setup before it really effected the clock. Very easy to get in the ball park. One thing that threw me for a loop is the side springs. I get the concept, soft means more mid corner rear traction. But when lowering the side spring rate to softer I had to dope less of the front too. Still trying to wrap my head around that one. Any way...


I have seen a few tuning guides on the net and there all good but I really haven't seen any hard fast rules. I think I have a few. Let me know what you guys think.



Front.
Caster: This is front grip. If you need more grip then move the upper arms forward. If its too much, move it back.
Reactive caster: This is where you want your grip. Going into the corner (10deg), even all the way threw the corner (5deg) or mid corner to exit (0deg).
Start with .018 front spring. If the traction is high or you have to dope heavy in front then .020's would probly be better.

Unless your having rear traction issues or your tires are WAY off then I would start with caster.

When you have that set, next is the side spring/shock spring combo. The two have a balance to each other where they work in side grip and forward grip evenly. That seems to be

Silver side/blue shock
blue side/gold shock... I would start here for stock/ss on carpet.
gold side/red shock.

A really good starting setting for the shocks is 30wt/30wt.


Set your side springs as soft as the lay out will let you. And by that I mean find the fastest, tightest direction change and see if the car goes threw it or if your waiting for the car to change direction. You shouldn't have to lift off the throttle for the car to change direction. Too stiff of a side spring and the steering will get twitchy right off center and it will start to throw the rear into the corner. This action starts to show up as double steer then gets worse. When I went from a gold side spring to a blue one, the car went a tenth faster. Then from the blue to silver it didn't get faster but it was more consistent. Any softer and I bet it would have slowed down. Pretty quick and easy to find the right side springs. Then fine tune the shock spring for the on-power steering you like.

There you go. Caster and side springs will get your chassis 90% there. Then fine tune the tires, aerodynamics and oils to finish it off.

DK
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