Tweak is usually when the suspension or chassis is unequal from one side to another and it causes the car to oversteer in one direction and understeer in another.
You need to make sure your suspension is equal on side to side. Like shock springs are compressed the same rate, droop screws the same length for starters before diagnosing the tweak. Once you get beyond that usually it is either the chassis top plate is loose or too tight or your shock oil is blown out one of your shocks from a hard crash or lots of barrel rolling on the track.
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