Same concept as the SVO. Its pretty much the same other then my is carbed rather then fuel injected. Its a blow thru carb setup and is a pain in the ass to tune and work with for that matter. lol. I'd show some pix but no cobalt guys probably care. lol

Sorry, back to the topic guys.

26psi.. Isn't that a little high for pump? I know the DI systems allow cars to run a leaner tune but I'd think the little K04 was just blowing hot air at that psi.

everything was so off...everything was past efficiency and out of wack, that little k04 is done with at 20psi. he was just happy he dynoed 270+hp with just a tune. it was done so unsafely though. i will see if i can find the thread so you can see the dyno sheets and logs

Here's a a link to the system we've developed for LNF in the Solstice GXP and Sky Redline. We plan to cover Cobalt and HHR next.

Billet Blow-Off Valve System

here is the thread
https://www.cobaltss.net/forums/show...ht=hhr+ss+tune

Wow...all this fighting on what a BOV really does. and alot of it is false information. Let me educate you all for a second.


A Recirculating valve which comes on most stock turbo'd vehicles acts in the same way a BOV does (essentialy). However instead of the air going up and out making a loud woosh noise, it is recirculated back into the intake stream. Why? Because the air is already metered. Recirculating valves are ideal for both performance and drivability.


Blow off valves let the air up and out into the atmosphere. Making a louder woosh noise.

Now, the main reason for either is to prevent compressor surge. Think of it this way, You got air travelling to the right...which spins the compressor say...down.

Now, without a BOV, your basically going to force slow moving air into it, which will in case slow the compressor down.


BOV's/Recirc Valves only purpose is to allow the turbo to continue to spin, vs stopping suddenly all together.

More then likely they'll be like.... Hey, I knew it was supercharged..! ha

I doubt ppl even know this thing is Turbo'd

Very nicely writen Turbo06Sedan. That was the point I was trying to get across just didn't word it as nicely. I got a racing ticket for the BOV on my mustang and had to write to the court how it always goes off and why.
And word gets around fast. Most people will know it is turboed. Also you will hear it in the exhaust

Ive already had several people ask me at lights if its the new turbo'd one, one guy asked me to romp on it so he could hear it! (and as far as I know I am the only one in the raleigh durham area with one) :). And that wonderful whine of the turbo under boost..... much different than a supercharger whine.

I agree completely and with your quotes I'm going to make my own statement:

All these people asking about blow-off valves as their first mod need to sell their cars because this car doesn't deserve to be riced out. By using the above quotes as evidence we can easily see that the only purpose a BOV could possibly serve as an initial very first mod -- is to be a ricer fag that makes cool boosted noises to scare other people. Unless you have this thing modded and you can back it up, then stop asking about BOV's. Every post I've seen about them is someone just wanting to know if there is one that "fits". They are never asking which they should get or why for performance reasons. They just wanna know if they can stick one on. We had people asking for them when the SS/SC came out for god's sake -- please stop being so lame. Tune the car, earn the respect, then scare the shit out of everyone because your car sounds mean and can back it up. Your car will sound mean if you do it right. Certain parts that make pretty sounds will become necessary. If all you wanted was "psssssht" -- get a civic, the parts are cheaper and you can make it look as cool as the SS/TC -- and that's all that matters to you anyway.

Ok now. Having a bov isn't ricer. I agree that just putting one on a completely stock car for the sound is stupid. Now I have one on my stang and there hasn't been one person tell me its stupid.

Calling things Gay:

Because anything you don't like inexplicably reminds you of homosexual relations. :confused:

thats why you move the maf post bov

Wow, that was SIX homo references in a post that ends with 'ass'. I detect some serious latency in this thread! :D :D

so out of this post it reads

Fag, fag, gay, fag, fag, fag, ass


lol someone has some deep rooted issues about there sexuality...

whys everyone gotsta be fags!?

Hey Mr. Hahn any idea when these BOV will be ready cause thats a nice setup for the solstice. Also would it even be beneficial to stock vehicles? If it is would it be beneficial for the auto on the HHR SS?

who ever said the injectors were maxed on the lnf are way out of the ball park.

The BOV maintains the spool by releasing boosted air that would push back in the blades and slow the turbo when you let off the throttle. BOV are not stupid, I think they are cool. I could cruise around town as see plenty of people with Atmo BOV running around in SRT4, Scobbie, Evo's ect. Are they all stupid, no.

To answer the orginal posters question, from the turbos I have seen the Recir valve (same function as a BOV) is built into the cold side housing of the turbo so I don't think you could remove it and add a BOV as easily as some boosted cars. Off course since it's so integrated it probably does a great job of keeping the turbo from surging and losing spool.

Also the post about releasing unmetered air is correct, unless the ECU is able to compensate for a BOV it will have trouble understanding why air passing by the MAF isn't make it into the engine, it will probably run bad and give a CEL at some point.

Some turbo cars use a MAP to determine fueling so the fueling is based on the boost pressure post turbo. This means if you release air mass via a BOV the ECU can detect and compensate. The GM cars use a MAF which measure the air before the turbo pulls it in, so when it releases boost the ECU can not handle that. There are lots of advantages to MAF over MAP, mostly in the accuracy area. MAPS rely on a table to reference pressure and RPM to determine how much air is entering the engine. So changing parts of the motor can affect that table and through your calibration out the window where a MAF can detect the addition air and compensate the fuel spark.

EDIT: I just read hahns post, so it looks like you are in luck, also this post is my understanding please clarify or correct me. Don't call me a homo as I am happy married. :lol:

There I edited my posts to keep from arguing. So how does the new cobalt compare to a srt4??? And how does the supercharged???

First mod I would do to the SS/TC is BOV. Personally, I like em. I loved mine in the SRT and I miss it. Gotta love how everyones head rips around to look at you when you blow by them.

LOL< thats funny

I said that the injectors seemed like they had a very high limit, the high pressure pump is what I said I think is limited.

150 L/hr seems like the max for da pump

i like the recirculating bov.... u can hear it spool and if u listen close enough u can hear it blow off jus not into the atmosphere that make ppl look at you and go, "did that car just sneeze?"

I agree :twothumbs a mother Fu*k!ng 10 :twothumbs