they push(understeer) more than a ball diff, so you have to tune it out of the chassis but once you do watch the lap times drop
. aslo the front tires will wear more and keep an eye on the front drivetrain, spools are hard on the drive components(cvd's, outdrives, ect.)
associated does make a spool part 1704 for the ntc3, but it should work in the tc3/4 as they use same drivetrain, but if it dont be inventive. pass the ca