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Old 08-05-2005, 07:18 AM
  #7994  
teamgp
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Join Date: Jan 2005
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No problem Jason. I love to test. Now hopefully I can translate it into a good finish for the upcoming Rockville, MD race. If the setup doesn't work at all, at least I have a better understanding of how all of these tuning options will affect the BMI outfitted FK05, which should allow me to dial it in quickly during Friday's practice day.

Thursdays test results:

Now that the car was hooked, with CS27's on the front and CS22's on the rear, I dialed up the EPA on my transmitter to see how far I could go until the rear end would brake loose. At 80% the arm of the inside steering block started touching the front anti-roll bar mount screw and the rear was barely giving a hint of initial over steer after getting on the gas.

Then the thought occured to me that I still had the QC2's punch control set to 5 for "mega punch" (gotta love those european guys vocabulary ) with stock motors. So I dialed it down to 3 and I found that I could now get on the gas earlier and the over steer was gone. But getting on the gas earlier gave me higher speeds exiting the corner and there was a noticeable abrupt push at the end of the exit arc where I assume the QC2 was letting go of the leash right in the heart of the double wind motors peak power (I have it geared just a tad on the high side). I dialed the punch control down to 2 and the push started to go away, but dialing it down to 1 for "smooth" power finally tamed the Fantom 10 x 2. I also noticed that the higher corner speeds was wearing the insides of the rears slightly so I reduced the camber from 1.5d to 1.25d. Keep in mind that with the shortest rear camber links and 3mm spacers under the ball ends, camber gain is very high and .25d is a big difference.

Next I chose to dial in the right amount of grip gained from the dampening. The car was already set at two holes open, so I clicked them over to one hole open (gotta love the adjustable Xray shocks & yes I know they are a pain for some to build though ) and the car started drifting noticeably on corner exit as I could see that all four tires were struggling to stay in contact with the road. I moved on to the other extreme and clicked all of them over to four holes open and the car was stuck in the corners like glue with a noticeable difference in scrubbing a lot of speed. Clicking them over to three holes open loosened the car up just enough for much faster corner speeds and with enough traction to provide a tighter steering arc than was present with the initial two holes open. With AE 40wt oil, this should be the equivalent of using Xray 30wt oil with all four holes open.

With one pack left and 5 minutes to spare, I threw on a good set of RP30's for grins and the car was in another class. Dialing down the punch control and opening up another hole on the shocks must have glued the rear end to the road like CA sticks foam to the fingers. And the RP's added steering that was equivalent to a slot cars. The cornering radius was cut down by a third on corner entry with heavy braking AND corner exit with a trigger happy throttle finger. Zero sliding in the rear and no pushing in the front should make late breaking for the inside pass more fun and less hair raising.

I took it with me to my friends house (Barbecue...MMmmm ) where the grip of the smoother asphalt was really low due to a little bit of sand. He's back from Iraq on two weeks R&R and of course I had to demonstrate the mean machine to him for a BRIEF minute. I was surprised to see that it coped well with the low grip as the car was still balanced with a little drifting action that was controllable with the throttle. I'd hazard a guess that for very low traction tracks, opening up the shock pistons to four holes or switching to white springs in the front and blue/green in the rear would give enough grip.

Updated setup:

http://www.teamxray.com/xforum/xform...7&setup=t1fk05
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