Tuning guide for a stable A800R/RR 
Tip n°3: A STABLE REAR END
Five ideas to try if you’re struggling with stability:
Dynamic toe-in gain. As the suspension compresses mid-corner, the rear geometry can work for you or against you. On the A800R/RR, you can increase dynamic toe-in gain by raising the inner pivot point of the rear toe arm. Concretely: move the rear toe arm to the upper hole on the rear bulkhead. As the car rolls, the rear wheels gain toe-in progressively, which plants the rear end exactly when you need it most: mid-corner and on exit. The car stabilizes itself so you don’t have to manage it.
Softer rear spring. If your car skids from the rear, try reducing the spring stiffness by 0.4mm. It might seem like a small change, 3.2mm to 2.8mm is a 95.4 to 91.3gf/mm reduction, so really tiny on paper. But on track it can make a noticeable difference. Your favorite driver’s setup sheet is a starting point, not a bible.
Be sure to use soft « S » springs inside. You can sometimes get away with soft springs outside, even though your car will likely be better supported on the normal springs. What rarely works are the normal springs inside, you’re guaranteed to launch your car into the stratosphere on the first kerb you attack.
Use shorter rear toe arms. Swap your stock AM23-R for the shorter AM23-1. This will result in a more locked-in rear. It’s a popular setting for the A800R/RR even for the max-steering-as-a-lifestyle-pro drivers.
More static toe-in. This one is a classic. More rear toe in = a more stable car. Don’t hesitate to go to 3° or 3.5° if needed. There is no trophy for who can run the least toe in the rear. Run as much as you need, no one’s judging 
. One thing to keep in mind: more toe-in costs you a little straight-line speed. It’s a trade but most of the time, the stability is worth more than the top speed you lose.
Three tips in, same conclusion: a car you trust is faster than a car you need to manage. That’s the whole philosophy of this project. Go to flowrmx.com to get your A800R/RR stability fix.
Follow this page for tip n°4 !
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