wot would happen if this was say, by passed, my brother reckons it wont do anything harmful, just make a wicked chatter noise of the wastegate

 

Kill the turbo i would think

 

Must be there for a reason !

 

Im no expert but as far as i know the wastegate is on the exhaust side and only opens at max boost the dump valve opens when you close the throttle both help to make the turbo last longer.

fit a atmo dump valve if you want some noise

 

na, hate the noise of the tshhhhhhhhhhhhhhhhh

its bad enuff with the noise of the air filter

 

RB5 - your brother is correct about the chatter noise. Removing the dumpvalve will also improve responsiveness when changing gears (contrary to popular belief the majority of the "whoosh" noise from VTA dump valves is acually all the boost from the intercooler piping escaping, which then takes time to build up again when the valve closes) however this will decrease the life of your turbo as it will get "shock waves" (for want of a better word) when you back off the throttle between gears.

A lot of older turbo cars didn'y have dump valves, but they've been added mainly to increase the life of the turbo.

Please search the archives for info - there were a couple of really long threads about it a while back - as I'm just re-iterating what was said before.

Cheers,

Andy