Originally Posted by
Stogie
That looks like a good setup, Brent... and not too far off what I'm currently running on asphalt parking lots (I'm just sprung a bit softer in the rear than front). I'm curious, though - you indicate that you're running the C21 topdeck. Is this a smooth track or is it a bit bumpy? I struggled the first time out with the topdeck on - the car got really unstable over rough spots. Finally tried taking the topdeck off and presto - instantly dialed in! (Unfortunately I figured this out after the Mains - oh well. I'm prepared for next time!)
So from what I'm figuring out... high traction and smooth surface - use the topdeck. Lower traction and bumpy surface - no topdeck. Does that sound about right?
I actually have not tried the car without a top deck yet on our track. I might try this next time we race, July 27th, to see how much of an impact it has on grip. Our track does have one decent bump in the sweeper which i sometimes have issues with the car breaking loose and this may help. However i have solved it with what i explain below.
I do agree with erchn on the rear being to soft. I ran into this problem at the Tamiya track in CA the first time i ran there. If the rear is to soft it will break loose very easily on bumps. My theory here is the inside tires lifts to much giving you less traction. When you stiffen the rear it helps keep both tires on the ground more giving you more traction.
One of the differences from my carpet setup to asphalt is stiffening the rear spring by 3 mm. So i run 4 mm gap on the top for carpet and 1 mm for asphalt. I know this seems backwards but it works.