Slash 4x4 Buggy 1717 6s

[RC-Monster Mike]

Looking good. Tires are just like you describe - the better traction they provide, the faster they wear out. Regarding front toe - zero degrees is pretty ideal. Generally speaking, toe-in generates better initial steering off power, but tends to push more coming out of the turn(on power). Toe-out is essentially the opposite, providing less initial steering entering off power, but much better steering on power. Of course many other things in the setup affect steering.
Rear toe-out is almost unheard of, as it generally created instability. Rear toe does create some scrub, but adds straight line stability(pretty important for high speed). If the rest of the setup is pretty rigid(minimal flex and play in the linkage, etc.), I like 1-2 degrees rear toe for high speed straight line work(3 degrees is the norm for off-road).

[Dafni]

Definitely must be a capable platform.

Some serious power you have there on your Slash. I'm amazed.

[Lizard]

Little update:


As it turned out, the earlier 93mph run with the XO-1 tires (geared to 112mph with 26/38) was not valid, seems like the tool I used calculated the values on it's own based on the location and timestamps and did not use the speedstamps.

Made a new measurement, this time with the GRP tires (100mph theoretically with 26/38) and reached 94mph. The XO-1 needs a 121mph gearing to reach 100mph, which means, the Motor is less loaded in the Slash. Would be interesting to see what speeds the Slash can go to with 121mph gearing, I would guess something between 105 and 110mph.


Also made some acceleration tests, it accelerates from zero to 90mph in about 4 seconds and needs about 300ft of space to do this

Now I'm thinking about putting something bigger in. What do you guys think, would a TP Power or Leopard 58x82 1420KV motor on 7s work with an XL2?


Topspeed 151kph / 94mph



Acceleration to 146kph / 90mph in 4 seconds:

Originally Posted by RC-Monster Mike

Looking good. Tires are just like you describe - the better traction they provide, the faster they wear out. Regarding front toe - zero degrees is pretty ideal. Generally speaking, toe-in generates better initial steering off power, but tends to push more coming out of the turn(on power). Toe-out is essentially the opposite, providing less initial steering entering off power, but much better steering on power. Of course many other things in the setup affect steering.
Rear toe-out is almost unheard of, as it generally created instability. Rear toe does create some scrub, but adds straight line stability(pretty important for high speed). If the rest of the setup is pretty rigid(minimal flex and play in the linkage, etc.), I like 1-2 degrees rear toe for high speed straight line work(3 degrees is the norm for off-road).

I think that was the effect I was having, it seemed more stable as long as you wouldn't touch the wheel, but when trying to correct a little, it would always be either no turn, or too much turn, which led to zigzag lines.

On the rear I have 3.5 degrees toe-in if I remember correctly, but I think the rear hub carriers can be swapped around to get 1.5 degrees, will try that sometime.

There is still play in the linkage and in the wheel carriers, need to find a way to reduce that.


Dafni:
Thanks, I'm amazed too how well this thing turned out :)

[Dr_T]

Hi Lizard, how's it going? Got the new suspension dialed in yet?

I was wondering if anyone here has some recommendations for diff fluids for on-road speeders. I read on-road racers typically use heavy or locked front diff and around 10k cSt rear diff. I'm working on an Inferno GT2, 5682 motor, center spool, RTR weight will be about 4.5 kg, geared for 90 mph and up (depending on what motor will be happy to pull for continuous use). I'll be running 2° rear toe (instead of stock 3°), as Mike suggested below, to free up some speed, but have no idea if I should compensate that with a bit of a lighter rear diff fluid in order not to lose too much rear end stability. Any ideas?

What would be a good starting point for rear and front diff fluid, yielding good balance between straight line stability and handling (I'm not talking about serious track use, I just don't want it to be a straight line speed runner only that does not turn well)?

Originally Posted by RC-Monster Mike

Rear toe does create some scrub, but adds straight line stability(pretty important for high speed). If the rest of the setup is pretty rigid(minimal flex and play in the linkage, etc.), I like 1-2 degrees rear toe for high speed straight line work(3 degrees is the norm for off-road).