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Whats the story with bov's on twin turbo rb26 engines?

Are twin bovs really needed, or even just single or is none at all fine?

Im currently running twin -5 turbos with no bov setup at all and Im just wondring if thats ok, or if it will eventualy kill my turbos or just possibly shorten their life?

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In reality it won't do harm, will just chew more fuel etc.

Without getting into a ridiculous debate, ONE of the reasons manufacturers introduced BOVs on turbocharged vehicles was to improve the longetivity of the item.

Im not sure what you freshies know these days, but 5 years ago buying a 200sx meant you would probably need to change the turbo at some stage. Now think back in order of popularity for fully sick rides, the 200sx is up there, as is its famous 'pinched hose' dose effect.

Get yourself a skyline (that has hardly been tampered with) with a stupid ceramic turbo with probably double the Ks of your old 200sx (in reality) and hey presto! Still running the OEM item isnt it?

Get a BOV put on, pretty much case closed scenario.

Aside from that they also have another purpose - to avoid compressor surge on light/low throttle.

Compressor surge = bad. As it is stopping the whole building of boost in the first place when on throttle as the BOV's leak at idle and light throttle.

Often people have noticed when changing to a 'hard pipe' kit, or taking the BOV's off and fitting larger turbos like 2530/-5s that they get comp surge uphill depending on throttle position.

So there is very much a purpose other than emissions/reliability.

Some users do have issues and have to return to the factory setup, some people dont. There are all sorts of factors from cams, piping choice & even exhaust flow etc.

Ahh te old BOV debate! I have no idea why people want to change something that works!

Aside from that they also have another purpose - to avoid compressor surge on light/low throttle.

Compressor surge = bad. As it is stopping the whole building of boost in the first place when on throttle as the BOV's leak at idle and light throttle.

Often people have noticed when changing to a 'hard pipe' kit, or taking the BOV's off and fitting larger turbos like 2530/-5s that they get comp surge uphill depending on throttle position.

So there is very much a purpose other than emissions/reliability.

Some users do have issues and have to return to the factory setup, some people dont. There are all sorts of factors from cams, piping choice & even exhaust flow etc.

You have just described EXACTLY what I am experiencing. Since going to the duel entry ARC core I had to block off my BOV's with a bung... So effectively I'm running no BOV's. It has created havoc with the tune. I was under the impression that all that crap would stay with this kit! It pisses me off that much that I am going back to a nismo single entry cooler so I can have my precious BOV's back.

Cut a long story short... Leave them as they are. Spend te money on something that improves your car... Not making it sound like a busted pelicans arse!!!!

No BOV's for me. Much better throttle response from part to full...ie out of a corner....compressor surge comes from the turbo spooling faster than the motor can injest it....The other surge is actually compressor stall.

Each to ther own. Mine is 90% track however

Matt

No BOV's for me. Much better throttle response from part to full...ie out of a corner....compressor surge comes from the turbo spooling faster than the motor can injest it....The other surge is actually compressor stall.

Each to ther own. Mine is 90% track however

Really? With mine blocked off it feels like the turbos practically stall. There is a significant delay when my boost needle rolls back around to 1.75 bar..... Interesting!

Matt

Why would you want to get rid of them for? I haven't heard another BOV sound as good as the GT-R ones and they flow enough for what most users are going to need anyways

my single-GTR BOV on my GTS-T sounds atrocious lol. Throttle-off sounds like I just kicked a pigeon.

Im running a Vipec ecu, and also the greddy hard pipe kit so the standard plumback setup is too much hassle to fit.

I originaly had a single hks bov in the cooler piping up near the plenum but It wasn't mine so I had to give it back to my mate.

Since removing the bov I have found slightly better throttle response. I was just keen to hear peoples opinions on if running no bov actualy does reduce the turbos life or hurts anything.......?

I was originaly having dramas with comp surge but since removig the bov that is no longer a major problem..

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