Bosch Diverter Valve (110)

[neonsox]

I recently picked up one of these:



I plan to use it as a BOV off the lower turbo -> intercooler hose. I can't get a clear answer on how this is supposed to be installed. The problem is that I've already JB Welded it into a pipe with the vacuum and bottom port running in parallel with the pipe. So the boost pressure will be entering from the side and exiting the bottom (which I put a filter on). The reasoning:

> The other reason I don't put the boost inlet to the bottom of the piston, is
> because if there happens to be a lower pressure on the vacuum actuation
> side/nipple, I don't want the valve cracking open with the boost pressure.
>
> On the contrary, if you do orient the valve in the opposite fashion of
> VW/Audi, you must make sure that the actuation signal/nipple sees the
> same exact pressure as the inlet so it's less likely that it will crack
> open and bleed off boost.

So which install is correct on our cars? This way:



Or this way:



Thanks!

[contraption22]

These are capapble of holding very little boost pressure.

[neonsox]

Supposedly, this model number (Bosch #0280142110) is rated to 22 psi, so I'm hoping it can hold the 13-15 psi I'm throwing at it.

[30 PSI SHADOW]

Your both wrong. Ive run these for the last 15 years on all my cars. I presently have one on my rampage. My black shadow pumped 30psi through these and performed flawlessly! Even rick diogo commented as being the best sounding and performing BOV
The boost pressure feeds through the bottom and vents out the side .

---------- Post added at 02:22 PM ---------- Previous post was at 02:21 PM ----------

Your both wrong. Ive run these for the last 15 years on all my cars. I presently have one on my rampage. My black shadow pumped 30psi through these and performed flawlessly! Even rick diogo commented as being the best sounding and performing BOV
The boost pressure feeds through the bottom and vents out the side .

[neonsox]

Can it function the other way around? I'm sort of committed since I welded it in wrong.

Edit: I used this page when I decided to weld it in.

[Juggy]

Can it function the other way around? I'm sort of committed since I welded it in wrong.

Edit: I used this page when I decided to weld it in.

every type of BOV or wastegate i have seen allows the pressure to push the valve UP when vaccuum helps relieve the spring.
youd basically be trying to force it back closed install the way you have chosen.
if your running 15-16 psi vaccuum, that means you are going to need more then 32 inches of vac just to try and get that thing cracked open. combine that with spring pressure and you will need even more vaccum. I dont believe its possible for it to open up

[ShelGame]

I ran the same one at 20psi - once. I ruptured the diaphragm on the first pass.

[30 PSI SHADOW]

How did you weld it? The body is plastic

[neonsox]

I used some black PVC piping for the tubing and Tee'd the valve in using JB Weld designed for bonding plastics. It was a putty and it cured within a couple hours. It is pretty solid and seems to have done the trick. It was gray, so I threw some plack paint on there to match it with the rest of the assembly.

I've been reading about these diverter valves all day and it seems the Audi and Saab guys use them both ways. By design, it would seem as though the pressure side should be on the bottom port pushing against the daiphram, but they argue that the top nipple also pushes down under boost causing the two to work against each other. When the pressure enters from the side port, the nipple also is applying pressure and the valve stays closed better.

I have no choice but to install it the way it is and see what happens. If it fails, I'll just reuse that old BOV I have and eat the loss.

[BadAssPerformance]

Or this way:



Thanks!

Yes.

There are (at least) 3 differetn part numbers that look identical. the one I had on my T2 Shadow has seen a peak of 27psi on the highway and 19psi in the 1/4, no issues until the rubber diaphram finally gave out last year.

I'd put it after the IC to try to keep it as cool as possible for longevity

[2.216VTurbo]

Can it function the other way around? I'm sort of committed since I welded it in wrong.

Edit: I used this page when I decided to weld it in.

Yes, you can run it the other way in fact I prefer them that way, kinda squeaks but holds pressure better IMO. I've run them on at least 5 set ups.

[neonsox]

Thank you all! Bill recommended the valve and if it works for him, it works for me. I just wish I had installed it as designed. Never a dull moment. But if it works on 14 psi and performance doesn't suffer, I'll just stick with it. I suppose I could do some cutting and flip it should it not pan out, but there doesn't seem to be clear evidence that it won't work effectively reversed. In fact, appearance-wise, it looks and fits better reversed right under the battery tray before the IC inlet. The plan is to hide the valve and maintain a stock appearing engine bay while protecting the turbo and preserving boost integrity.

[Mopar318]

I have about 10 of these. cost $1 at the junk yard.

[Force Fed Mopar]

I ran the same one in my GLHS, and later in my Daytona. Had it hooked up the way it shows in the first pic you posted. Held 20 psi no problem. Grabbed it off a Saab years ago

[Big_P]

I used the same one with my 600 at 18psi. I had it set up just like a BOV.

It was also JB-welded, and held up great!

[neonsox]

So another day, more research on the topic. I found this on my hunt. The "normal" side is how some of these valves came installed from the factory on certain Saab and Audi cars, so it's the reverse of above (just to be more confusing).



It almost looks as though the reverse install would seal better but not necessarily lift off the seat better. I'm conflicted as to whether I want to take everything apart and redo it or just leave it. If the spring in this model is rated 22 psi, I would think 15 psi of vacuum coming off the brake booster would have a hard time pulling up on the plunger. Add the slight pressure from the turbo (even in vacuum, correct?) and that could make the opening that much harder as previously stated.

[wheming]

If you have an air compressor you can always mock up a test.

The problem Gus and I had was the diaphragm distorts drastically under high boost. Apply a 20psi signal to it and you can see the diaphram ballon out into the (designed) discharge port. Apply 25 or 30 and it'll be worse.
Unless they redesigned to use a different diaphragm material.

Bottom line, if you aren't exceeding the boost pressure which the orignal application used, you should get normal service life.

When we used them 15 years ago they were cheap, light, easy to find, .....and garbage.



my android sent this for me using Tapatalk...

[Force Fed Mopar]

So another day, more research on the topic. I found this on my hunt. The "normal" side is how some of these valves came installed from the factory on certain Saab and Audi cars, so it's the reverse of above (just to be more confusing).



It almost looks as though the reverse install would seal better but not necessarily lift off the seat better. I'm conflicted as to whether I want to take everything apart and redo it or just leave it. If the spring in this model is rated 22 psi, I would think 15 psi of vacuum coming off the brake booster would have a hard time pulling up on the plunger. Add the slight pressure from the turbo (even in vacuum, correct?) and that could make the opening that much harder as previously stated.

Actually the reverse install would open easier, it has the boost pressure pushing it open. The normal install (which is the way I ran mine) might be harder to open, but it will hold more boost I think because the boost pressure is helping to hold it shut. It also equalizes the pressure on both sides of the diaphragm, which will prevent the ballooning effect wheming mentioned and should give you a longer service life. Certainly mine hasn't ever given me a problem over 8 years, and it was used when I got it off the Saab (which also had it installed in the normal fashion).

It looks to me like the reverse install would be for low boost cars, and the normal install for higher boost.

[neonsox]

Actually the reverse install would open easier, it has the boost pressure pushing it open. The normal install (which is the way I ran mine) might be harder to open, but it will hold more boost I think because the boost pressure is helping to hold it shut. It also equalizes the pressure on both sides of the diaphragm, which will prevent the ballooning effect wheming mentioned and should give you a longer service life. Certainly mine hasn't ever given me a problem over 8 years, and it was used when I got it off the Saab (which also had it installed in the normal fashion).

It looks to me like the reverse install would be for low boost cars, and the normal install for higher boost.

Interesting, so if I'm just running standard 1 bar pressure (up to ~14.7 psi - intercooler drop), it might be best to run it in the "reverse" way shown in my latest picture to protect the turbo. If I plan on turning up the boost, I could leave as is ("normal" in the last pic) for better sealing and longevity.

In that case, maybe I will just leave as is and see how it goes. Of course, that might change in 20 minutes after more reading...