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BOV/Wastegate Info

1265 Views 5 Replies 2 Participants Last post by  CloNeGTS
Alright, I have to admit that I don't know many details about turbo systems. Of course I know the function of blow off valves and wastegates, but I don't know much about the types of both or what are considered the better brands/styles.

Anyone have any good info? I've tried finding FYI sites on search engines to no avail.
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CloNeGTS said:
Of course I know the function of blow off valves and wastegates...
maybe we could start with basic definitions for those (like me) that have little experience with turbo engines...

a bov relieves boost pressure to protect the turbo. when you lift off the gas, the throttle slams shut and boost pressure quickly builds. the bov releases this pressure. some bovs pass this excess pressure to the air (the "pssht!" or chirping sound you here on wrc); some bovs recirculate the boosted air to the input side of the compressor (the side that is normal air pressure).

a wastegate relieves pressure on the turbine (exhaust) side. it is used to allow exhaust gases to bypass the turbine. this is necessary to prevent the turbine from over revving at high RPMS. (the diverted gases just goes out the tailpipe and don't contribute to spinning the turbine.) therefore the wastegate is what determines the max boost you can make. wastegates have cooling fins since they manage hot gases.

in summary, both are used to protect the turbo. the bov protects the turbo when you quickly get off the gas; the wastegate protects the turbo from over revving when you refuse to get off the gas. :) the bov is located on the on the input side; the wastegate is located on the exhaust side.

okay, where am i wrong? :oops:
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CloNeGTS said:
...but for now it's off to bed with the fiance! :wink:
so you know, you put that one high and slow over the plate. i could make all kinds of jokes about blow-off valves and wastegates. :eek: but i'll be good, i'll resist. [quick, somebody knock this outa the park...] :D 8)
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