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Old 09-30-2007, 07:25 AM
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dlampe dlampe is offline
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Join Date: May 2004
Location: centralia, IL
Cobra Make & Engine: B&B cobra (sold), Hurricane HMS1002 (sold), Kirkham 289 FIA, (sold) RCR GT 40(sold) SPF GT40 2122(sold) Hurricane HMS2002, (sold) RCR SLC (sold) GTR on the way!
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Default RCR gt 40 track test & chassis setup (results)

RCR 33 track test & chassis setup

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The car has finally crossed over from the build to the tuning phase.







I spent the day at the track today so I thought I would write a little report. Before I get into the performance of the car let me share some basic chassis set up data for you. I weigh 205lbs and I had 12 gallons of fuel, 6 gals each side.

Ride height F 3 3/4 R4.5
Lower front A arm angle 3.5 deg.
Wheel weights Lf 650 Rf 589 Lr 763 Rr 715
Front% 45.6
Left % 52
Total 2717lbs

Springs front 550 Rear 375 lbs (wheel rate around 280 front and rear)
Ackerman 1deg toe out in 10 degs of turn

Toe F -1/16 (out) Rear 3/64
Camber F-1.9 R -1deg
Caster F 5.8 R5.6deg

bump steer left front bounce and droop
inch change
1 = 0.005
.75 = 0.002
.5 = 0.008
.25 = 0.002
0 = 0.000
-.25 = -.017
-.5 = -0.034
-.75 = -0.55
-1 = -0.07

bump steer right front
inch change
1 = -0.012
.75 = 0.001
.5 = 0.003
.25 = 0.005
0 = 0.000
-.25= -0.007
-.5 = -0.02
-.75 = -0.41
-1 = -0.052

These settings where achieve through a lot of chassis set up and a lot of trial and error.

To the track..........

This car drives so well that there is really no words to do it justice. I ran with a group of 75 Porsche's. I ran most of the day in Group 1 which is the advance group. I was consistently able to lap every car in the group over a 20 minute session. The car went where I turned and behaved very predictably. I was consistently faster than I had been the year before in my cobra. The car was tight with this setup and had a tendency to push in the corners although you could kick the rear end out with just a little pedal. I am going to take the rear springs up to 450 to loosen the car a little but I will also need to increase my front bar to correct a little boy roll issue. The goal is to net out a car that is a little less tight but not by much. I have a universal joint problem and the fuel pressure is running a little high for the Webers. I don't think I will make it back to the track tomorrow but today was a screaming success. For those of you just finishing your car, let me tell you that you will feel like a rock star when you go to this type of event. Everyone will want to come over and talk to you. People are fascinated by these cars. If anyone has any specific questions, just ask. I feel like I really bonded with the car today and let me say it again- There are no words to describe how well this car handles.

For those of you who wanted to reserve judgment on RCR until there were some on the track, Here you go.
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Last edited by dlampe; 09-30-2007 at 09:42 AM..
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