as title,what is the best dumpvalve?i have a 2wd standard sapphire,in the future i will be buying a big spec engine with bigger turbo etc,but im not sure what dump valve to get in the meantime?all the jap 1s sound crap,they whistle.baileys are too hissy,collins are still dumping after you change gear and are too poor sounding,my pal had a 4x4 sapph a few years ago and when he changed gear at full boost his sounded like a whip cracking followed by a nice noise,whhhaaaaaatooooooshhhhh,say that quickly and you will get an idea!!!ha ha,cheers.