it also effects other things than just turn in. caster angle is also changed, which effects on power steering and stability of the car. less castor can make a twitchy car in a straight line (more turn in). more caster helps the re centering and overall stability and on power steering. also your front axle type will need to be considered as well. if you are running a front diff, then you will have already increased turn in over a spool. something to think about.
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