The 4 spring uses 8 weight levers and allows for a smoother (more gradual) engagement in my opinion.
This can be an advantage for higher torque engines like an animal or limited mod / stock appearing, etc.
Both can be made to work very well with the right set-up.
I see no real disadvantages to the 4 spring, but the 6 spring is by far more popular in stock classes.
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Thanks and God bless,
Brian Carlson
Carlson Racing Engines
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35 years of service to the karting industry ~ 1Cor 9:24
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