EXT2Rob

My Feedback: (1)

Hey why is it that some cars, mostly in the off-road catagory I'm guessing, are the rear wheels toed-in a degree an a half or so? Yet, I've seen ads for "Factory Team zero-degree rear hub carriers". Or in some cases it'd be a rear arm hinge blocks with a 0-degree angle to the hinges.

Common sense might tell one that having zero toe would be better, since the tire would be tracking straight. So why the toe on the rear tires?

FuelCoupe

Does it track straight ? I know the plastic carriers from traxxas allow the rears to distort in weird ways. The only reason I could see for toeing in the rear would be distortion under power, e.g a degree of toe in may come back to 0 degree under power, sort of like how the camber changes under power. Either way I dont  see it making any difference other then adding or taking resistance to the motor. Having said that I am not really in the know and there may well be a valid reason for running toe in on the rear.

Foxy

A car with straight rear wheels is particularly difficult to hold in a straight line at speed and/or on an uneven surface. When you factor in that we also employ toe out the front for turn-in, you REALLY need the rear toe in to keep the car going straight and more importantly, change direction predictably.

You ever skied (as in used Skis)? Remember the first thing they teach you? The plow foot position which instantly stabilises you? Same deal here.

Even only a little toe in will create enough stabilising effect to keep the rear end following the front, but more is usually better. 1/8th buggies run 2 degrees plus.

i8tweety

My Feedback: (11)

When I was racing dirt oval with my rc10GT I ran 4 degree rear toe to help keep it straighter under acceleration. Zero toe will cause the rear end to step out every time you lose traction and spin the wheels.

EXT2Rob

My Feedback: (1)

Ah, ok.  Interesting.  Thank you.

Wow, sometimes people toe-OUT their FRONT wheels?  Better turn-in, eh?  But what does that arrangement do to its straight-line tracking?  Does it make it more difficult to hold a straight line?

OvalRacer99

Wow, 4 degrees. Idid just the oposit, I went with 0 to get the rear end to "stepout" in the corners and not plow the front end.
In oval racing, loose is fast but harder to drive. Used an oval truck body with tons of downforce so it was quite stable at high speeds!
Rear toe can be a great tuning tool as it helps the rear end either plant if your car is loose or you can use it to loosen up the rear if it is pushing.
Back when I first got into racing (late 80's) we had adjustable a arm mounts to make rear toe quickly adjustable without needing to change parts.

FahrtAutoRC

All of our off-road racing setups run around 1* of front toe-out

It does little to disrupt straight line tracking, as long as they're done even and trim is reset to help even it out.

i8tweety

My Feedback: (11)

I was running a high speed banked clay tri-oval (400 ft lap). As the track wore in over the course of the day, it would get develop a dusty surface half way through a race even with watering between rounds. Tap the brakes to initiate pitch of the truck and manage drift with throttle.

i8tweety

My Feedback: (11)

I was running a high speed banked clay tri-oval (400 ft lap). As the track wore in over the course of the day, it would get develop a dusty surface half way through a race even with watering between rounds. Tap the brakes to initiate pitch of the truck and manage drift with throttle.

Foxy

For normal racing on a normal track, ALWAYS toe out at the front. Yes, it makes a HUGE difference to turn-in. Toe settings at the front have almost no effect on stability (within reason), the toe at the back is responsible for that.