crlytm

IN my Kyosho book it says use 1000wt in rear diff but I hear of people using 10000wt and 20000wt oils. Wouldnt these wt oils lock the diffs up tight, what does such heavy wts achive?
Thanks for the help.

Rysuleod

iTrader: (1)

I may be a knucklehead but I feel like the thicker you go in the back the more your rear end behaves like a solid axle. The wheels turn at similar speeds no matter if you are cornering or not. This gives you good traction in a straight line but in a turn it allows the car to rotate from the back since one tire or the other is always breaking loose.

I run 257 (front to back) in a XB8R at my track to good effect. It's low traction with lots of turns. I've tried 353 and didn't like it. With the 7000 in the back, my car will rotate from the back on power allowing me to powerslide through corners.

Smarter people than I helped me out with diff stuff in a similar thread on here: http://www.rctech.net/forum/showthread.php?t=124829

This is what the XB8 manual says:
Front
Thinner
· increases steering into corners (off-power)
· if oil is too thin the steering may become inconsistent,
especially it can lose forward traction
(and steering) during acceleration out of corners

Thicker
· increases stability into corners during braking
· increases steering on-power at corner exit


Center
Thinner
· front wheels unload more during acceleration
· decreases on-power steering (reduces oversteer)
· easier to drive on rough tracks
· if a high-power engine is used you could waste too much
power and sometime “cook” the oil in the center differential
because it “overloads”

Thicker
· more all-wheel drive effect
· better acceleration
· increases on-power steering (reduces understeer)
· better suited on high-bite, smooth tracks
· car can be more nervous to drive especially if a high power
engine is used - you might need to be smooth on the throttle


Rear
Thinner
· increases cornering traction
· increases steering into corner
Thicker
· decreases rear traction while cornering
· reduces wheelspin

crlytm

Thanks for your help. Will Look at that other thread you recommended.

cwalters

iTrader: (4)

thinner diff oils in the rear will help the car hug corners through entry and mid corner. But you won't have good on power throttle pull from the rear of the car coming out. Thinner will help the car hook up a little better coming out. If the track is rough or slippery try thin oil like 1000 or 2000. Same for the front. We like to use a little balance. In my buggy I run 5000/7000/2000 front to rear in most cases. On a tight track, like indoors or hardpack groved or slippery tracks I will sometimes go lighter in the front and rear to keep the car steering tight. Only problem with that is that the front will tend to not pull the car out through the end of the turn on power because it is diffing and not locking. In that case lighter would be like a 3000 or 4000 in the front still 7000 in the middle and 1000 or 2000 in the rear. There was a really good article explaining the effects of diff tuning by Chad Bradley in I think XRC September issue if you can get ahold of one. Main thing is don't run what everyone else is running, read, learn and experiment and run what feels right to you. I was in the same boat one time and with a little homework and trying different stuff, I am always hooked up!!! Good luck

crlytm

Thanks Mugenchad will try and get hold of that mag. My local track is rough and loose have been using 3/5/2 FtoR last meet tried 5/7/2 liked the steering on exit but to much rear loss of traction. 7000 centre seems to be to aggressive for our track will try 5/5/1 next meet. temper aggressive bite from centre diff allow rear to diff a little more hopefully allowing me to hook up a little more, if I understand what you guys have been telling me. Will keep on experimenting and learning will get there. Thanks

cwalters

iTrader: (4)

If your track is loose and rough try 1000 in the rear and leave the 3000 in front, that will take care of your looseness in the rear.

Good luck, Chad