TC6 rear whips around on right turns - fix how?
 

My indoor TC6 on carpet... I've changed nothing on my setup & not crashed but now my car when accelerating into/out of RIGHT hand turns spins out like its on ice... the rear whips around uncontrollably. Turning left it holds great. What could be wrong?

I pulled out the loose carpet fibres. Nothing appears broken. To the touch the shocks seem to depress/respring out properly.

Ideas? :confused:

Sounds like your car is tweaked (chassis twisted a little) or has different shock spring preload settings.

1. Loosen all of your top deck screws.

2. Tighten them.

3. Do the same for the lower chassis.

If your chassis was tweaked this will straighten it out.

Use a ride height gauge to check your ride height on all 4 corners. adjust your shocks to make the height equal.

Pull out your inner hinge pins and see if they are bent.

Make sure you are running ~3 deg of toe in per rear wheel.

Tweak is a good first guess. The recommendation I have is pull the wheels/tires and disconnect the shocks and sway bars. Put it flat on the setup board and see if it sits flat. Either way, loosen the top deck screws, then retighten while it is on the board and flat. Reconnect the shocks, put on the wheels and set ride height. If the adjusters are not even, you still might have some tweak. Set your sway bars and recheck ride height. Set droop, then remove wheels, put on setup gauges, and reset your camber/toe.

I would pull the springs off the shocks and make sure you have equal rebound as well.

Also, make sure nothing obvious is happening, loose bottom screw or something under the car dragging. Also make sure the wheels spin without hitting a shock mount/ball at full lock, etc.

Check your shocks. Could be your left front shock is low or out of oil causing it to be too soft and digging in which could cause the right rear to lift and break traction. I had a ripped bladder this past weekend and my car doing the same thing.

Hand your car to your local fast guy and have him "square up" the car for you.
Way too many possible causes of this.

D.

If my car does that and I'm not able to locate the obvious cause for erratic handling in two or three "pit-stops" after checking all the usual (aforementioned), then I just take the car apart completely and rebuild it very carefully. It might sound like overkill and time consuming but in my modest experience it saves time... it could be a swollen shock o-ring, a slightly bent hinge pin, a dead ball bearing... a hundred things. Doesn't take that long at all. Plus, by going the full rebuild route you gather experience on what can go wrong on your car.

check your tire gluing maybe ? sorry if that's too obvious :blush:

If you did not change anything setup wise, then check/reglue all your tires, and check your rear Bearings closely ! Don't mess around with other setup adjustments, specially if the car was fast. I've found that the rear AE Bearings sometimes get pitted, and it can cause some wheel lockup when subject to lateral load in one direction, while being fine in the other direction. Only one bad bearing can cause this, and make you think your diff was bad, or your tweak/shocks also went sour...You'll have to feel each rear bearing for grittiness, and also test the new Bearings that you'll replace them with: better be safe than sorry.....

Do Not Rebuild your whole Car ! At the most, you'll have to upgrade to Acer ceramic Bearings (on all your wheel axles only) the problem does not go away. Also tc6 original Bearings were a real problem back then. Check the TC6 thread, and you'll understand, but I think it was mainly the wheel axle Bearings.....

Rebuild the car, just for peace of mind, it should be done on a regular basis anyway and if it's anything to do with tweak (my diagnosis for your problem) then you'll eliminate that, bearings, or any other problem (checking for straight pins, tyre gluing etc) you'll find any of those problems.
Plus you'll have a nice spotless looking car again for when you run next.

check your steering throw

Others have given lots of good ideas. Switching tires left to right is an easy first thing to try. Otherwise you just need to keep looking at everything til you find it. My personal guess is a bent hinge pin.

Check your roll center mounts because they do move and can give u uneven droop

Changing Bearings + reglue tires = 1 hour
Rebuild the car = 10 hours
9 hours of practice = priceless !!!!!

10 hours... Your not rebuilding a space ship tiger....