For those of you who are famillar with the location and orientation of the DV, take a look at this pic.
I went to do my 710N install, and while looking at the original one, I was surprised to see that it was installed backwards (at least I'm 99% sure it was). I installed my new one opposite of this, because I was so convinced that it was backwards. My car had a new turbo installed before I got it, so there's a good chance it was done at that time.

Pretty ironic... someone in the current 710N thread asked if you could install it backwards for possibly more boost. I told them that would not be a good idea.

If by some stretch of my imagination this pic does NOT show it installed backwards, then it would make no difference if it were installed either way.

 

this pic is from underneath and its installed corectly....

And yes it makes a difference if you instal it backwards alot of boost would escape.

So what your saying is your new one is installed backwards!

 

I agree. I think it's installed correct in that pic. If you look inside the DV, you can see that if the boost gets strong enough, it will open the valve so the boost doesn't get too high. If it is installed backwards, it looks to me like it wouldn't release any excess boost except when the vacuum is high and damage could be done to the turbo. I can't see how it would relaese too much boost like Chriz says.

 

thats because you dont understand how a DV works... PM me if you want an in depth explanation of how it works

The vacuum is what opens the vavle to release boost. if its instaled backwards the presure side is on the bottom of the piston and pushes it up releasing boost so... it will still release boost while is backwards.

 

Wait, I'm confused. (Not hard to do) So, you're saying that the boost should be going in to the side of the 710N? I installed mine so the boost is in to the bottom of the 710N, thinking that it is also like a pressure relief valve. If the boost gets too high, it will open a little, letting just enough boost out to keep it below the determined boost limit. If the boost goes into the bottom of the 710N, the only thing that could open it would be the vacuum. Which means it functions only in vacuum situations. Am I cottect?

If it is installed so the boost goes into the side of the 710N, what is there to keep boost under control when not under vacuum?

 

"If the boost goes into the bottom of the 710N, the only thing that could open it would be the vacuum. Which means it functions only in vacuum situations. Am I cottect?"

No, if it goes into the bottom once you're at higher revs and higher boost the spring will be overcome and dump boost before the specified limit.

"If it is installed so the boost goes into the side of the 710N, what is there to keep boost under control when not under vacuum?"

The spring, it keeps the valve closed until vacuum is applied to it in order to open it. The boost won't open it on its own as it's acting on it from the side not underneath.

I'll second that in your pic it's installed correctly, if installed the other way as soon as you put boost into it it'll open up the valve and boost will leak.

 

I'm really surprised to hear that the pic is installed correctly! Yes slim, my new DV is currently in backwards. (not for long though).

Another thing: if the boost is unable to open the valve if it's installed as shown, then how can there possibly be any difference between a 710 and a 710N valve? As shown, it's merely a vacuum operated valve with no "safety" or pressure relief feature.

An interesting observation though: After installing my 710N (supposedly backwards), I also installed a small digital boost gauge. I have NO idea what kind of boost I was getting before, but I'm seeing no more than 5-6 psi now, regardless of engine load or rpm's. I'll see what happens after I turn the 710N around.

 

youll get the same psi.

on the bov you put the boost side into the bottom. when the throttle body is closed this creates pressure in the intake hose; this pressure opens up the BOV. which in turn shoots air into the atmosphere or into a recirculatory hose.

leak where? the whole system is pressureized where would the boost go? its a recirculatory valve, if it leaks it puts it into the system, thus losing no pressure. if it was bov then it would leak to the atmosphere.

plus you kinda have to be an idiot to install a BOV backwards.

 

Leak out to the unboosted pipe before the turbo surely?

 

LOL! It woudl take some serious engineering to install a BOV backwards.
After turning around my DV, I can now hold 7 psi after a quick test-drive. Because of the way this DV installs though, I still fail to see the difference between a 710 and a 710N.

On this BOV, the boost pressure does not open the valve. It had an incredibly stiff spring in it, and only opened up with vacuum. It may have opened under higher boost pressure, but I was only running 10 psi.