As far as varying loudness, it just depends on how much boost you have at the point you shift and how QUICK you shift. When I'm racing and I shift quicker than normal they tend to be much quieter, shorter spurts. When I'm driving at normal speeds and shift w/ only a couple lbs. of boost you can hear them very well(they actually scare people). On a side note, how many washers are you gonna put in? I also had none in, then I switched to 3 in each and I actually noticed a gain in power. I think they were leaking between shifts due to the lack of spring pressure.
