- Kyosho ZX6 - Roger Mills - High Grip Astroturf Track Setup Advice - Apr. 2015 -

I've been doing a fair bit of work with the ZX6 to get a base astro setup that is both quick and easy to drive when running shortie configuration. I've tried the car with saddles and it is naturally more stable and smoother over bumps but nowhere near as agile and fast over a lap as the shortie car on high grip tracks.

For me the key things with this car is that it generates so much natural steering that you need to tame it a little in order to be supremely confident that you can really push on in a wheel to wheel racing situation whilst still having a car that gives fast laptimes when in qualifying mode.

To achieve this it seems that the main points are:

1) increasing the front track width, this helps to smooth out the high speed steering whilst increasing the instantaneous tire loading to give good direction change and bite at lower speeds, hairpins etc. Bout seems to be about optimum, going wider dulls the high speed steering a little too much, especially in the wet.

2) remove the front anti-roll bar which makes the front end a little safer when pushing really hard as it will collapse into a push on the very limit rather than dig in and roll over. Probably due to not having as much weight over the front end as the ZX5FS to keep it planted (but equally that is why the ZX6 has so much more steering than the ZX6).

3) laying the front shocks over helps smooth the car out on very high grip, making for a very stable and predictable feeling, does need smaller front piston holes though to get the right damping balance between static and pack. I've used the Kyosho piston blanks and drilled to 2x1.5 but you could use the AE pistons with a 0.4mm shim under them.

4) rear damping is really key on this car, far more so than the ZX5-FS2 as due to the comparatively rearward weight bias the rear damping also has significant effect on the way weight transfers across the front of the car. 2x1.7 seems to be the best for most situations however when the track is very bumpy there is a benefit to going to 3x1.5 (drilled Kyosho 3 hole pistons) and going up 50cst in oil rear oil. This keeps the rear end a bit more planted over ruts but gives very similar steering feel to the 2x1.7s

5) personally I find that increasing the front kick up helps the car carry speed on faster sections and helps the car transfer weight forward under hard braking which really helps rotate the car through the slower corners but equally helps generate a little more rearward transfer to generate a bit more forward drive.

The reason I'm using AE springs is that I personally want a front spring a fraction stiffer than an Xgear orange when running without an ARB, Xgear orange fulls part way between AE red and orange. I can't explain why but the car feels more balanced with an AE spring on the rear when using one on the front than running an Xgear gold which is essentially the same rate as an AE green (~2lb/").

To get to this point I have run enough to have worn out the centre drive line of the car, this is not based on 25 minutes track time like some setups you'll see ;)
I've also been lucky enough to have been able two back-back this car against most of the current 4wds with top drivers setups on and can honestly say that, for me at least, the ZX6 is the best of the bunch in shortie build due to it's balance of steering and stability.

I've not run on carpet since settling on this base setup however I suspect that this will work well on carpet too with +100/150cst oil in the front and +50/100cst in the rear. I have run the car with identical geometry but shocks in the middle hole on the front wishbones and 2x1.6/2x1.7 piston combination and the car was very quick but lacked a little 'sparkle' which I'm sure will be cured by the front end changes.

Hope this helps people get the best out of the car.

Kind regards,

Rog