@theatriks, haha, I'm really happy to hear that it changed things around! I went testing again yesterday and made huge progress yet again. Please read below!
As you all might have found out the TF6sp is quite a handful when driving on carpet and it's obvious that the handling of the
car needs to be improved. I've been out testing with John for a couple of times now and we think we have made quite some
progress already. Due to a rather 'huge' breakthrough we had yesterday we thought it'd be a good idea to give you all a small
update of the things we've been working on.
The most significant and important change we made is changing the weight balance of the car. The main problem of the car is
that it's quite tricky to drive on carpet. By moving the motor and the battery forwards the front we found the car way more stable and easy
to drive compared to the regular layout. It improves the handling in every single way, it smoothens out the ride without compromising
on steering while corner speed is being increased!
Just a few small modifications are to be done in order to run a different weight balance. First off cut the front Lipo holder in a way that
just the horizontal bit is still in the car so the lipo can slide to the front and rear but can't touch the belt. Then create a new lipo holder
on the rear side of the lipo that pushes the lipo forwards by 3.5mm compared to the regular position. The lipo will now close the front
tape gap, this is not a problem.. just tape the battery like your normally do.
The motor needs to be more towards the front too. Just put it in the most forward position that's possible on the motor mount and use the
right (bigger) pinion and (bigger) spur.
To transfer the weight even more towards the front I moved the entire suspension 1mm backwards. All the shims are now in front of the
suspension arms. Keep in mind: remove 1mm from ackermann too if you do this to keep the same angle. Add 1mm shim on the front shock
mounting (lower) and remove 1mm on the rear shock mounting (lower) in order to keep the shocks perfectly straight.
Last but not least, I moved the servo 2mm towards to the front by taking out the 2mm spacer that most people run on their std. mounting posts.
Rear diff position
The car felt rather 'pushy' from the rear on carpet mainly because of the diff positioning. The standard (low) position puts the rear driveshafts
under a rather extreme angle which effects the way the driveshaft operates badly. When you accelerate a driveshaft wants to straighten itself
out due to lateral forces. Considering the angle the axle makes with std setting, straightening out becomes very difficult which creates friction and
the car to feel as nervous as it does.
To eliminate this you have to run the diff in 'high' position. This allows the driveshafts to operate under a more horizontal like angle and
smoothens out the ride.
Another very important improvement we made is the wider rear settings on the car. By using the widest option on the rear-rear block (which is F outside)
and the best suitable rear-front insert (I use B outside) to get the desired toe-in angle the car gets easier to drive, way less likely to traction roll and much better
Very simple, to eliminate bump steer just run 2mm underneath the steering knuckle.
The Yokomo blue and pink springs seem to work very well on carpet. A bit less likely to traction roll then the Tamiya springs that a lot of TF6 drivers
use. Pink front, blue rear.
As most of you will know I'm always running the short arms. John has done some B2B testing and it seems that the shorter arms give more traction
and the car feels more 'alive'. We think this is the best option to run as long as you don't suffer from traction roll. When the traction is super high and
traction roll is a big issue then the longer arms might work better. They generate a bit less traction then the short ones.
Most brands are using the same bulkheads in front and rear of their cars. As you know our rear bulkheads are connected with 6 screws where
the front ones are held into place with just two. I drilled some extra holes in my chassis and fitted 2 front bulkheads in the rear too. John used the regular
rear bulkheads and cutted off the 'extra' post. We both feel the car is better balanced with this configuration.
As some of you might have spotted on RCtech already.. I modified my servo mounting to operate in the same way the new Tamiya/Yokomo/Xray etc.mounts
For explanation and pictures please check: http://www.petitrc.com/reglages/kyos...Track20121117/
Ignore the setup! Improvements have been made and the latest setup has been added to this post!
The bottom plate of the car is touching the motor which effects the flex in a negative way. John has milled down the area underneath the motor on
our chassis plates so it's able to flex without touching the motor.
Use the old TF6 upper bulkheads to lower the shock tower by a tiny bit.
If there are any questions, please feel free to ask!
Vasco (and John)