Compressor Surge? Help

[2.5T_/<ouki]

Hey All,
I'm thinking my turbo has compressor surge pretty bad, however i am unfamiliar with what it actually sounds like. I can hear my actuator/turbo "blow off" louder than my HKS BOV. I have to really slam it for the BOV to chirp, otherwise its just a measly little sound....

How do i go about fixing compressor surge? Id really like to NOT kill my turbo/engine. Here are two videos i took. Hopefully you can hear the sound. This is my turbo not my bov.

My BoV has it's own dedicated vacuum straight up to the Intake Manifold, and the wastegate has it's own vacuum source straight to the nipple on the hotpipe.



IMG_0726.mp4 video by rbkoukis14 - Photobucket

IMG_0727.mp4 video by rbkoukis14 - Photobucket

[Mitsubayati]

That's surge for sure. Normal problem is that the BOV isn't opening in time and the pressurized air isn't being evacuated quickly enough. thus, that air looks for the best opening which is the turbine wheel and while going back through it causes it to slow down abruptly making the sound you hear.

If you have another BOV that you can swap in, try that and see if it fixes it. You can check to make sure that your BOV is working correctly by hooking up the vacuum port to a vacuum pump and pumping it to 13 inhg (inches of mercury). If the valve opens at that point then it is working properly. Are you running a recirc. setup?

[slider2828]

uhh really? adjust the BOV..... its in the manual. increase the length of the screw

[Edwin562]

cant you just soften up the tension on the BOV spring?

[2.5T_/<ouki]

Hrmmm.....Could have sworn it was adjust correctly. It was probably my brother messing with my car while i wasn't there >:|

Thanks for your input guys, i really appreciate it. Ill give it a shot and let you know ^.^

[2.5T_/<ouki]

Just checked the little screw on the BOV and it's pretty much all the way out. It has to screw into the BOV about a quarter of an inch before it even touches the spring....

I'm guessing this means the BoV is defective?

[fliprayzin240sx]

Sounds like its not opening enough...then again its a HKS SSQ, they all sound like poo.

[Edwin562]

time for a new BOV....

[2.5T_/<ouki]

Yeah, i was guessing it was the BoV.
When i put my hand in Front of the BoV and rev i can feel the air coming out and i don't hear the surge, however once i start to drive and build boost then it comes right back!

Could having that little "reducer" piece that comes with the BoV actually have something to do with it not opening up enough?

"The little black piece"
I actually am using this because i didn't have a hose that was long enough at the time, so that little piece is sitting in between the BoV and my Intake Manifold.




Thanks guys, i really appreciate the help.

[Sileighty_85]

that "little black piece" is just a Filter.

if its clogged it could cause problems

[Kingtal0n]

Where is your blow off located? The farther away from the compressor the more surge you will generally hear.

Also, the vacuum line should be dedicated (no T's) and it should be very free flowing (those filters sometimes hurt the response)

So before you start shaking your fist at the bypass valve, consider using a dedicated vacuum line, and possibly relocating the bypass closer to the turbocharger.

The HKS bypass is a nice piece if its truly HKS, and not a chinese replica.

[2.5T_/<ouki]

My blow off valve is located about 7" away from the throttle body on the cold side; iirc it's better to have it on the hotpipe side if you are running a recirc setup so you push it into the intake before it comes back and reaches the turbo.

My BOV has it's own dedicated (no T's at all anywhere) & my wastage is connected to the nipple on the hotpipe side. I suppose it could be my BOV, i never hear my BOV at low rpms even with then screw almost all the way out, I just hear the surge, sounds like it's coming out of the intake

I'd really like to fix this issue. I appreciate everyone for helping.

[EsChassisLove]

my shit surges even if Im at -15 vacuum. Shits ridic. Like wtfff bro.

[Kingtal0n]

The HKS piece is nice because it reduces the tendancy of the bypass to open around idle- thus solving many of our atmospheric bypass valve issues. Unlike the typical push valve that could open intermittently around idle and cause issues with a MAF car.


On the other hand, you wind up situations like the one above. the turbo is trying to push air into the plumbing and technically, as designed by the factory, the bypass SHOULD be open at idle! And indeed, a bypass valve open at idle, is NO PROBLEM when the bypass is recirculated back into the turbocharger's inlet.


So here is the ultimate compressor surge fix: Install a recirculated push type bypass on the hotpipe, exactly like the factory did. DONE, PROBLEM SOLVED.

If you insist on using the HKS piece, the only thing that might help is moving it much closer to the turbocharger. The distance from the turbocharger DOES increase the likeliness of surge. Just think about it: when the bypass opens, how does the air get AWAY from the compressor? How far does it have to move to actually reduce the pressure in the plumbing? Remember that the turbocharger is still filling the plumbing with air- trying to compress the air, so your tiny HKS bypass opens literally miles away from where the problem really lies: at the heart of the compressor. You think you can dump the entire contents of your intercooler through that tiny hole quick enough to relieve the pressure applied by the compressor the instant you lift your foot? No, your HKS piece is just a noise maker over there by the throttle body. And thats assuming there is nothing actually wrong with it.

[reallygood101]

i had the same issue so i opted to get the synapse bov and it wrks awesome

[Zacho]

You won't kill and engine with that. I get the feeling few in this thread know what real compressor surge is.

Is this a genuine HKS unit? or knockoff

[2.5T_/<ouki]

It's an HGayS blow off valve.

I'm thinking Kingtal0n has a point there. I've always seen it on the hotpipe side.

[EsChassisLove]

Please demonstrate the difference betwen real surge and fake.

10+ pounds per square inch of air running back to your compressor wheel seems pretty real to me.

You're right it won't kill an engine. Just a turbo. Lol

[cotbu]

Real compressor surge, surge line of compressor map can only be reached during boost.
Flutter dump, aka compressor surge happens off throttle main cause improperly adjusted B.O.V!

One can be dangerous the other may dull compressor blades or worst case, cause the shaft to break. which could be a pain in the ass as well!

[2.5T_/<ouki]

I've adjusted my BoV countless times to no avail! I have tried every length every setting possible all without positive results.

I'm kind of wanting to move my BoV over to the hotpipe side to see if it eliminates more surge as Kingtal0n said. Would this be a better choice or a new BOV

[EsChassisLove]

Move it, get a new bov and recirc it. The HKS SSQV is nothing but a noise maker. Chirping chirping chirp

[cotbu]

How much vacuum is the line pulling? You could always get another bov and move it and all but how do you feel about not solving your problem, when it's so simple?

[Kempz]

nothing more than a show off valve lol, move it and recirc it.

[slider2828]

Did you get a real one?

[2.5T_/<ouki]

No, i got an HGayS blow off valve. I'll probably try and get it moved over tomorrow.

[fliprayzin240sx]

Get a better BOV. I vote Greddy Type-R Bov.