AVO BOV Installed (With Instructions and Pix!)

Finally I got my very expensive AVO BOV. Installation is relatively stright foward, even a dim-witted individual like myself can muster through this without any major hiccups. Proper instructions along with some pictures is included in the box, but I'd figured some members much like myself enjoy looking at pretty color pictures, so here it is. Tools required: 1) Phillip Screwdriver 2) 10mm socket and Ratchet 3) 3mm allen key 4) Standard Clamp [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1828.jpg[/img] Once you got all the necessary hardwares, pop your hood(Duh!) -Remove 4 phillip plastic clips that holds the engine cover [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1826.jpg[/img] Once the engine is exposed, focus on top right corner of the engine bay. - Disconnect the vaccum line(the small one) - Remove 2 10mm bolt(Gold) - Press on hose clamp with left hand , and disconnect the recirculation hose from the OE BOV in a twisting motion with your right hand holding the BOV. [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1827.jpg[/img] Now the OE BOV is out of the way this is what it should look like. [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1837.jpg[/img] Here is a pic of OEM BOV vs. AVO BOV for comparison [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1838.jpg[/img] Before we install the AVO BOV, inspect the item itself. - Make sure the base plate is aligned with factory mounting point, if not, remove the 4 base screws with 3mm allen key and realign manually. [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1831.jpg[/img] Once that is done, if you want to go for the 50/50 mode, then you would want to remove the backing plate. 3mm allen key will make quick work of removing the two screws that holds the backing plate. This is what will allow you to hear the audible "whoosh" when letting off the accelerater. With the plate on, you will not hear anymore sounds or noises than you would with the stock BOV. [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1833.jpg[/img] After all that is out of the way, proceed to mount the BOV. DO NOT forget to install the gasket piece that AVO provide you with. The gasket itself is an OE Subaru part, however, in this case, it requires slight trimming in order for it to fit for our cars. The gasket should be precut before it is send to you, however, in my case, I recieved an OE gasket which does not fit. I emailed AVO and the problem was addressed immediately. Here is a comparison between the gaskets. The top one is the cut one which we will use, the bottom one is not cut which is of no use to us. (Note: There is metal material inside the gasket so cutting it yourself without proper tool is going to be nearly impossible.) [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1832.jpg[/img] Installation is reverse as removal. - Mount recirculation hose first, make sure the BOV pipe is as far in the hose as possible and secure the end with the OE hose clamp. - Align mounting position with the gasket between, and hand screw the 10mm screws in. - Make sure the BOV and gasket is properly aligned and proceed to secure the two 10mm nuts with your socket and ratchet. - Reconnet the vaccum line with your hand, and Voila! Completion! When completed, it should look something like this. [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1844.jpg[/img] On top of the BOV there is a 4mm allen screw with a 13mm nut that determines the position of the BOV diaphram. DO NOT TAMPER WITH THIS. According to AVO, the position of this nut is preset to most applications, so your car should run best with its current setting. (Stupid me thought this screw was sound adjustment, so now I am trying to set it back to stock setting- trial and error) Moving on, with the engine cover back on, you can hardly notice the presence of this new BOV. [img]http://members.cox.net/kashiwa/kikkoman114/IMG_1845.jpg[/img] That's all for now folks. As soon as I get more miles and experiences with this BOV I will write a review of this item, and hopefully that will help in determining whether to make this purchase or not. If you have any questions, please feel free to pm me, I am no expert, but will try to do the best I can to help. Cheers!

Nice job explaining the install. How much is the new BOV and what gains do you expect (per the manufacturer)?

[quote name='bluesuby']Nice job explaining the install. How much is the new BOV and what gains do you expect (per the manufacturer)?[/QUOTE] It was $320 shipped from Japan and I expect to maintain stock drivibility and gain the satisfaction from the sounds this thing will emit when I am operating it behind the wheels.

tutorials are always nice, thanks for taking the time to show us! good pix too

Have you noticed any performance improvements from your new AVO blow off valve? When you lift throttle to shift, blow off valves are supposed to open up to prevent the pressure between the throttle plate and the turbo from slowing down the turbo, and once the throttle is opened again the blow off valve is supposed to close to keep boost. On some cars the stock valves may not open fast enough, resulting in turbo slowdown from backpressure, or not close fast enough, and cause poor throttle response from loss of boost, or simply not cope well with higher than stock boost levels, especially from aftermarket turbos. A good aftermarket blow off valve can improve performance under those circumstances. Has the AVO blow off valve resulted in crisper throttle response or reduced lag between shifts?

I'd be very interested in whether this has increased throttle response and/or reduced turbo lag. SBT

Help! I need advice from fellow members! With so far only 1 day with this new BOV, the car has been running like crap. - I can hear audible boost leak when accelerating not at WOT between 2,500 rpm to 3,500 rpm sporatically. - The car's rpm at idle dances up and down, and ocasionally stalls when coming to a stop. - Feels like the engine is loosing power, especially in between shifts. - Engine boggs around 2,500 rpm I spend the whole entire afternoon tuning with the 4mm nut on top of the BOV trying to get the right setting. Can anyone here explain to me exactly what this screw does and how can I go about getting my car running right? Does anyone else on this forum the exact same BOV that can give me some pointers? If this is the way this $320 BOV is going to make my car run, then I'd much rather have the stock ones back on and live without the sound in between shifts.

From the looks of the top screw your running close to 100% atmosphere....thats your problem. Also, do you have a MT or AT???

[quote name='BoxerGT2.5']From the looks of the top screw your running close to 100% atmosphere....thats your problem. Also, do you have a MT or AT???[/QUOTE] In the quiet words of virgin mary... do you know what you are talking about?

[quote name='kikkoman114']In the quiet words of virgin mary... do you know what you are talking about?[/QUOTE] Yes..... :D

well, with the stock turbo, i really doubt this BOV will do anything other than give the user the dope sound. the stock BPV will do a fine job of keeping air away from "slowing down" the turbo, as was my experience with the WRX. $320 is just WWAAYY too much $$ to spend on a sound for me. i once spent $100 on a Forge for the WRX, and that was def worth it. couldn't justify spending this much on it, although i wouldn't say this would either help nor necessarily "hurt" the performance of the car.

[quote name='BoxerGT2.5']Yes..... :D[/QUOTE]Then please enlighten me and elaborate your statement, for I do not possess vast automotive knowledge and turbo know-hows to understand the basic function of a BOV. Explain to me just exactly what this little nut does and how much should I screw this, so far you are the only person who appears to know something that has answered my cry for help on this thread. If you can determine that I have improperly install and/or tune this BOV just by looking that the pictures, then please shed some light. There is nothing more I want right now than to retain my factory drivibility and not feel like $320 wasted. Oh, I have a MT by the way.

Kikkoman, When you have some time, let me know your phone number in pm, and I'll have Ross talk with you to troubleshoot the problems (probably some time in your evening). Cheers, Paul Hansen [url]www.avoturboworld.com[/url] [url]www.apexjapan.com[/url]

Try adjusting it to be 100% recirculating and see if the problem persists. If it does, check the vacuum line connection.

So this one is completely adjustable eh? I don't know which way the nut turns, but it definitely sounds like you need to adjust it closer to 50/50 and go from there.

What's your status my friend? Have you talked to Ross or Paul, yet?

I'd like to add some advice here - the black bolt on the top, it should be screwed in as far as it will go. Not all the way in, about as far as it can go and you can still screw the nut that keeps it tight on as well. This will cut down on the noise from the BOV when it is venting, but that is because you are keeping the pressure level up. If you adjust it outwards, it will vent more often, but that is also lowering the level of pressure that it will be holding back as well. Too far out and it won't work properly at idle, especially due to the greater manifold vacuum pressure that the 2.5 may be creating. Other than that, just make sure that the hoses are tight on the BOV, and make sure you haven't pulled them loose from their other ends on the car. Cheers, Paul Hansen [url]www.avoturboworld.com[/url]

So far if the nut is left relatively unscrewed, the car will sporatically leak boost when under normal acceleration under 4,000 rpm. With the nut screwed in as much as possible, the boost leak is diminished but the car boggs really hard around 3,500rpm and under. Very unsmooth. Ocasional unstable idle is present at both settings, and sometime the car will stall completely. I tried tons of runs with the the smallest adjustments in between and still have yet acheived acceptable results. I don't know if this is something that can be settled over the internet or emails, but if I need to take it to professional tuners and have it done... so be it. Got any recommendations around OC and LA areas? Right now the stock BOV is back on the car, because I cannot deal with a $30,000 car running like a $3,000 car.

is the car running the way it was before the change in bov .now that it is stock..ie no damage to the motor..

[quote name='X-RAY']is the car running the way it was before the change in bov .now that it is stock..ie no damage to the motor..[/QUOTE] BOV isn't gonna harm the motor.

[quote name='bluesuby']Nice job explaining the install. How much is the new BOV and what gains do you expect (per the manufacturer)?[/QUOTE] Loss in power, but awesome sound to scare off the kids and make all the girls scream with ecstacy :lol: Keefe

[quote name='Xenonk']Loss in power, but awesome sound to scare off the kids and make all the girls scream with ecstacy :lol: Keefe[/QUOTE] If I wasn't so cautious of rattles I'd install a bass shaker under the passenger seat first :D

[quote name='Autophysics']On some cars the stock valves may not open fast enough, resulting in turbo slowdown from backpressure, or not close fast enough, and cause poor throttle response from loss of boost, or simply not cope well with higher than stock boost levels, especially from aftermarket turbos.[/QUOTE] Today's stock BOVs are designed loosely.. hence they recirculate and dont hold boost very well. How do I know this? Unplug the recirculating hose from your stock BOV, the car will have a rough time at idle (it might even just stall) because of the pressure drop rate. I was trying to help a friend to come up with a way to re-engineer the stock bov on the WRX to make it atmospheric.. but I gave up on that idea because I would have to crack open the darn thing and replace it with a harder spring. An atomospheric is best used if your car tends to run near the leaner side of the AFR and that you have a turbo that is cranking up some serious CFM (not just PSI).. an example is a T77 turbo (it's big, a REALLY BIG turbo, for those never seen one, you can stick your head in one) at 4 psi.. sure it's not a lot of PSI of boost, but it moves soo much air that the air can really fill up quickly in the piping and produce a really high PSI surge that can overload a stock recirculating BOV setup (a stock recirculating BOV setup is to take as much air in and keep cycling the unused air back into the flow path until the engine is ready to gulp it all down). It can also overload on the rest of the turbo or mechanics and bend a fin if the BOV is too strong or tight.. just imagine all that air with nowhere to go? It's not always backpressure, it's really about total pressure within the air intake system (and hope your wastegate and factory boost solenoid is smart enough to sense an overboost situation and open the wastegate to stop the turbo from spinning to create any more boost). That's how the development of atmospherics came into play in racing trim since the turbo can just crank out a lot of air in matter of a split second through the maze of intake pipes. The only time when you worry that your BOV isnt closing fast enough is when it's not closing at all, causing to have low boost and overworking the turbo. Most stock BOVs are pretty loose enough and can hold a decent amount of boost. It's when you start cranking boost well over the specified spring rate the BOV has. I dont recall what is the specific boost limit for the stock BOV, but an example of another BOV is the HKS SSQV BOV. It can handle up to 24 psi of boost before it starts to vent out. HKS offers stiffer springs for their BOV so that it can handle 36 psi (28 to 29psi is 2 bar that's some crazy stuff) .. HKS Racing BOV can do as much as 40 to 90 PSI.. so unless you are really cranking some PSI on the diaphram, I doubt an aftermarket BOV will have a positive note for its use on a stock engine and turbo.. ... ... ... oh wait, it does, it goes "WHOOSH/PSSSH/PHSSEWWW/BOOM/GOBBLE-GOBBLE/DRUM-ROLL" (and whatever other sound I missed) and it's a total bling factor in stock form. :D It's the new age "wolf whistle" to pick up girls on the street ;) Keefe

I was asking if the car runs normal after he changed back. to see if he got a bad bov from the vendor so i can see how the vendor handle it.. so i know if i want to order any thing from them. or if it was a problem with the car...

[quote name='Xenonk']Today's stock BOVs are designed loosely.. hence they recirculate and dont hold boost very well. How do I know this? Unplug the recirculating hose from your stock BOV, the car will have a rough time at idle (it might even just stall) because of the pressure drop rate. Keefe[/QUOTE] It idles poorly because you have just created a large vacuum leak :lol: I would bet a vacuum leak is also the problem here. Checkeverything and make sure there are no leaks and that the beautiful piece of jewelry is not adjusted so that it is open the the atmosphere (and causing a vacuum leak) at idle. Good luck.