Ok, I installed the BOV Onto the lower IC pipe.  Now, when I let off the gas, it still uses the wastegate and the BOV does not open.  What could this be??  Could it be that the BOV is crushed, or do I have to hook it up to something?!

when the wgs cuts boost via ecu (rev limit/knock/or eng prob) or taking your foot off the gas the waiste gate dumps the excess air so the bov is not necessary.   You would have to have an aftermarket wg (overiding the stocker) and boost controller for it to work.  In stock form without a bov you can clearly here the wg purge the excess air when you take your foot off the gas especially at wot.  i am sleepy so I hope thats correct :?:

It needs to be hooked to your map sensor. Put a tee on the map sensor line and connnect the B.O.V. to it.

Quote from: 1trucavalierwhen the wgs cuts boost via ecu (rev limit/knock/or eng prob) or taking your foot off the gas the waiste gate dumps the excess air so the bov is not necessary.   You would have to have an aftermarket wg (overiding the stocker) and boost controller for it to work.  In stock form without a bov you can clearly here the wg purge the excess air when you take your foot off the gas especially at wot.  i am sleepy so I hope thats correct :?:

Sleepy, SLEEPY! Wake up!

:)

Actually, the WG can't dump the extra air, but the extra exhaust. THe sound you hear is actually the compressor wheel being hit by a pressure wave from the throttle body. When you take your foot off the gas, all the air that WAS going into the engine, has to go somewhere... RIGHT BACK TO THE TURBO. So your compressor wheel which was turning near 150,000 rpm gets slammed to a stop. The BOV gives this air a place to go so it doesn't hit your compressor wheel and try to stop your turbo.

that doesn't sound good, i mean really, with an air filte upgrade it sounds like a bomb going off. So would you guys recomend a blow off valve? obvisouly a boost controller is not a recommend way to try to reduce the wear created by our turbo's.    Thanks in Advance,

I just received my BOV ('92 Eclipse) and will be installing it this week. If I go through the gears with the 5-speed with just a filter on the turbo inlet it sounds really cool, but I know I am killing the turbo with the instant spin-down without a place for the compressed air to go! Chris A is absolutely right...you go from 100,000+ RPM to 10,000 in a flash! Our turbo's use a suspended oil bearing, not ball bearings or even a bushings on the shaft. So just imagine how much it torques the impeller shaft everytime there is boost on one side and back-pressure on the other! Auto-tranny cars still cause this condition, but not normally as extreme or as often as a manual tranny car as you are constantly closing the throttle body changing gears. The waste gate only relieves so much back-pressure in the exhaust side only... 8)

I got the BOV to work a while back, I just connected it to the intake plenum with a t-fitting for the boost gauge too.  Nice "Woosh" when I let off the gas, sounds like a ton of air and feels like it to when I put my hand infront of it.  I will never run a turbo without one again, it shot my bearings.

Does anyone know why it is suggested to use an g1 mitsubishi eclipse or talon BOV?  I have also been thinking about this mod, and after hearing all this great feedback, I am really considering it in the near future.

The BOV's rom '90-'94 Tsi's are of a pretty good construction. The other years were made from plastic.

so how much do they usually run? I suppose you have less turbo lag with one then since it isn't forcing to stop, plus you get less wear i'll have to get one.

I have seen them run anywhere from $35-$55. You need to make sure it is a "1g" bov with the mounting flange! 90-94 were the best ones as redturbo90 said they were all metal construction. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1855105632 Do a search on ebay for "bov". Just realize that we have no mounting on our TGP's for a bov and you will need the flange and to get someone to weld it on for you... 8)

Junk yard, you'll find a ton.  Or go to DSMtalk.com and do a search for BOV's.  They do not need to be crushed either.

cool, thanks guys. I just have one more question can you manually set the blow off value to get rid of all boost?, it might be a dumb idea but i would really like to be able to run my car without boost most of the time. Thanks Again,

Quote from: Black Pheonixcool, thanks guys. I just have one more question can you manually set the blow off value to get rid of all boost?, it might be a dumb idea but i would really like to be able to run my car without boost most of the time. Thanks Again,

THAT would be the wastegates job. The blowoff vlave just gets rid of the shockwave when the throttle closes. You can make changes to the wastegate to limit the amount of boost you want.

is that pretty easy to do, i know its simple to keep the waist gate closed but to keep it open do you have to like pry it up or something, i would perfer something as easy as a on/off type switch or lever. Any Ideas,
Thanks,