SCAccent

Just ordered a tial, but thought I would tell you about my ebay bov purchase. Nothing but junk! Recently the b*tch just stopped releasing pressure and i'm getting compressor surge.



Yeah, the fluttering from the air coming back out of the turbo.



I took off the BOV and tried to press the valve in and it was extremely difficult, last time i took it off, it was like butter.



I force it, and WATER comes out of the vaccuum fitting.



I kept pressing and got all the water out and it's still a b*tch to depress. tried adjusting to the spring also to no avail.



I don't know how to take that b*tch apart, otherwise I would do so, but I'm thinking the spring is rusted, along with grime and sh*t in there.







stay away from ebay knock off pieces of crap! my tial should be here Wednesday.

turbosocks

.. umm why would there be water in your BOV in the first place?



and if the spring was rusted or something, keeping the BOV shut, because of water that somehow got into your engine, how would that be the BOVs fault?



do you have any pictures of the ebay BOV you had?

tibbytib

I'm still rockin my ebay BOV. Had it for the last 4 years. I do admit, there are nicer pieces out their. I just happened to gamble and it paid off that I got a decent knockoff BOV.



I agree with socks, not sure why you are getting water in their, unless its simply MASSIVE condensation. Oh, I just checked your profile and yep, you live in a humid damn place!!! Not sure if that could cause your problems entirely though. Maybe. I live in a very dry climate, so I have had no issues like that here in Colorado.

steelcoffinx3

A similar thing happened to me after driving in the rain for a few days, the rrfpr diaphragm got filled with water-total lean out , but don't worry flutter won't hurt the turbo anyway.

turbosocks

the flutter can actually damage the turbo in the long run. compressor surge is no good, specially under higher boost levels.



where do you think all that compressed air goes when you shift?

the other way, and back out the compressor inlet.. not only slowing the wheels down a ton (which can result in alot of lag when you accelerate after shifting) but possibly spinning the wheel the opposite way.



obviously, no matter how little, the air forcing the wheel to slow down rapidly and spin the opposite way it going to put more stress on it.. more stress = wear.. more wear = less turbo life

steelcoffinx3

The turbo is subject to double the pressure (in typical setups) spooling the turbo up in the exhaust manifold when you floor the gas at high rpm so how is half the air pressure slowing the wheel back down stressing it anymore? And for lag, the turbo might not slow down as fast(but still pretty fast) but the bov is pissing boost away that has to be built back up, one manual car was 2 sec slower around a track with a bov. http://www.autospeed.com/cms/A_1457/article.html

turbosocks

should be pretty simple to comprehend why its more stressful.. its twisting it the opposite way that its wanting and was spinning.



the stress of spooling it up is spinning the entire shaft/wheel assembly from a standstill (slower rpm) one way, not going from 80k rpm to wanting to spin it in the opposite direction.



with a BOV, the turbo slows down naturally when you shift, which means really no stress. without a BOV, the 10,12,14,30psi you have in the charge system wants to go out the only exit.. back through the system, putting torsion stress on the shaft.



torsion stress = bad



pissing away boost that takes hardly any time to build back up isn't going to hurt pretty much anyone. most turbocharged vehicles aren't competitively racing anyway, especially on here. not to say that anyone on here doesn't competitively race, but 2 seconds on a ~1min 40sec track (taken from the article) is hardly worth putting more stress and reducing the life of a 600+$ turbo.



2 seconds slower = 2% slower around the track..



not to mention but 2% is a pretty slim margin of error as even with or without the BOV, i doubt the same driver could hit identical times in either condition.



and yes, professional race teams don't use BOVs.. they are competing, and they have huge budgets to replace the turbo every race if they want to.



regardless if it actually slows it down enough to spin it backwards (eg: long shift) its still putting the torsion stress on the shaft. I would rather my vehicle be 1-2% slower (negligible in my opinion [unless you race competitevely; which you would have funds to replace your turbo if anything did happen] ) than knowing that I am putting un-needed stress on my turbo.

steelcoffinx3

2 seconds is huge (20 car lengths @100mph) 20 hp won't be worth 2 seconds. Nobody has proven that some air pressure slowing turbo down is going to damage it, it's just speculation, plenty of people run for years with no bov, it's just something else to go wrong.

Stocker

Compressor surge: Bad It can kill thrust bearings, compressors, and even cases.



Dramatic example of a busted case: http://www.casting-repairs.com/Cantr...mpressors.html

Further reading:

http://autospeed.com/cms/title_Geoff...4/article.html

http://www.allsentra.com/viewtopic.php?f=30&t=2777



Surge - is the point at which the compressor cannot add enough energy to overcome the system resistance.[3] This causes a rapid flow reversal (i.e. surge). As a result, high vibration, temperature increases, and rapid changes in axial thrust can occur. These occurrences can damage the rotor seals, rotor bearings, the compressor driver and cycle operation.

http://en.wikipedia.org/wiki/Centrifugal_compressor

steelcoffinx3

That's surge under load not just forcing shaft to slow down.