So I tried the valve both ways and it definitely makes a difference. When the fitting on the side is connected to boost the ringing sound goes away almost completely. It is now a higher pitched hissing sound when the valve opens. I also experimented with a stiffer spring today and that also changed the sound; it eliminated the part-throttle ringing (or hiss depending on how it is connected).

At any rate I'll be running it with the boost on the side connection from now on. That whistle was getting to be annoying so I am glad there was an easy fix. Thanks Pat.

I did a back-to-back comparison and video taped it but the sound quality is not good at all and thus does not capture the difference in sound. It is not worth posting the vid clips, sorry.

Glad something good came out of this thread. My sound was nothing like subtle. I could hear a metal to metal ping sound well over my engine sound with the top down at a 75 MPH shift. It would make people walking on the side of the road stop and look waiting for parts to start falling out of my engine bay.. It was nasty.. On a good note I have a local guy that is taking my forge valve off my hands. He has an A4 1.8t and thinks he can get an O ring for it. I'm selling it for about 50% of what I paid which was 50% of the original owners cost. I made sure he knew about the issues I was having and the missing o ring. I guess for $40 bucks it was worth the chance to him. I'm just glad it's going away.

Yeah no o-ring in that bottom piston area would allow the piston to strike the body hard. So it is not just a seal, it is also a bump-stop. I can see how it would make a really bad noise with that o-ring missing.

I'll bet if he gets an o-ring for it and runs it with the boost connected to the side he will be happy with it. Since you had metal-to-metal contact I would tell him to check the seal surface on the piston and on the body surface to make sure they are not damaged or have burrs. That would tear up a new o-ring pretty quickly.

Thanks for the input I just PM'd him your exact words. it is scared a bit.. I think a little sand paper and some time will take off the burrs. It’s scared opposite the side port just below the first o ring so it makes sense.. I only ran it for about 20 miles like that so hopefully it will work out for him.. He is picking it up tomorrow before work it turns out he works like a block and a half away, Louisville is a small town.

We'll my apologies for assuming you had it installed incorrectly but I will say that, as can be evidenced by ZX-Tex's post, the ringing sound from backwards installation is a real thing and an internet diagnosis of a sound is nearly impossible. The words you used to describe the sound are the same I read from people running the valves backwards.

Have the person that bought the valve send an email to sales@forgemotorsport.com asking for a rebuild kit for the 007. We send them out for free, includes a new piston, all the o-rings in the valve and a packet of grease. Or if the body of the valve is too damaged we can send him a new valve. If that's the case tell him to send a few pictures. Or he can send the valve back to us to inspect and we will either rebuild or replace depending on what we see.

As for that picture you posted... neither Grossman Tuning nor Image Auto Detail are Forge Dealers. They must be buying through someone in our dealer network. The instructions must have been drawn up by either the company that you bought the valve from or the dealer they got it from as we don't include installation instruction with the 007, just a guide on how to tune the valve with the springs and shims.

Thanks.. i'll send him this info...

BTW there are install instruction posted on your website with pictures..

http://www.forgemotorsport.com/valve.pdf


Those are the same ones that came in the box with the valve

Interesting. I've never seen that before. That thing predates my employment with the company... we don't even make the valves pictured any longer and I know that in the past 2 and a half years we've never supplied those instructions with any of our valves... although I've always been bothered by NOT including them.

I'll update the photos and tell the guys that assemble our orders in the UK to start including them. Hopefully save me a few tech calls each week on how to install the damn things.

OK go to the BOV link in my sig for updated pictures of how it is installed now. After switching the inlet and outlet and installing the heavier spring I drove it some more today and I am much happier with the sound. The valve does not open up as often, but it still opens up far and fast enough at hard throttle cuts to prevent compressor surge. And the part throttle whistling is gone.