I actually found that my car ran worse with it reversed. It was more hesitant and boost felt less severe...something to think about. I personally think having it reversed is illogical in terms of it's function. The piston in the DV should be pushing the presurrised boost air downwards into the TIP, in standard fitment this is exactly what it does when the vacuum drops the piston. In reverse, the vacuum is pulling the piston open at a sideways angle, allowing the presurrised air to escape through a smaller outlet into the TIP and then when the vacuum drops the piston, it's shoving it back through into the charge pipe.
I'm no expert but that's not my understanding - the vacuum pipe is the little one on the top, reversing the valve means swapping the two larger pipes around so the side one is in the TIP and the bottom one is in the bottom. Therefore the vacuum still acts on the piston in the same way. I thought that the vacuum (when applied to the top of the valve) worked to overcome the pressure of the spring, thus opening the path between the two large pipes and allowing the charge air back into the TIP.
If that's the case then it seems logical to me to explain the boost issues you had with your valve in reverse - in this orientation the boost is pushing up on the bottom of the piston, if your spring isn't strong enough to resist that pressure then the boost could potentially push the piston up far enough to allow some of the charge air back into the TIP.
Have I got that completely wrong?
I'm no expert but that's not my understanding - the vacuum pipe is the little one on the top, reversing the valve means swapping the two larger pipes around so the side one is in the TIP and the bottom one is in the bottom. Therefore the vacuum still acts on the piston in the same way. I thought that the vacuum (when applied to the top of the valve) worked to overcome the pressure of the spring, thus opening the path between the two large pipes and allowing the charge air back into the TIP.
If that's the case then it seems logical to me to explain the boost issues you had with your valve in reverse - in this orientation the boost is pushing up on the bottom of the piston, if your spring isn't strong enough to resist that pressure then the boost could potentially push the piston up far enough to allow some of the charge air back into the TIP.
Have I got that completely wrong?
yeah thats bang on, im running a mapped lc with yellow spring in reverse, i find the cycle time quicker ie, the dump is dropped quicker, and closed quicker since the aid of the boost on the piston makes it easier for the vac to lift the piston,
99% of turbo diverter valves on all other cars, run in what us 1.8t owners call reversed, with the boost acting on the base of the piston, i think even on a diaphragm type valve having boost act on the perimeter of the rubber diaphragm does'nt seem logical to me, plus with the forge 007 fitted the right way round the boost pressure is acting on the o-rings as well as the seal to the TIP, putting more stress on them,
ive possibly put too much thought into this, but hey im a pneumatics engineer whos usually working with 150psi +,
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so your saying reversed????
IM GETTING LOST
tyrer said:so your saying reversed????
IM GETTING LOST
Seriously, just put it on the normal way round. Tried and tested it works fine and then leave it at that
i have had mine both ways (when i had the BMC), and yeh, you will hear a distant chirp...im sure with my open cone now it will sound louder. At first it is irritating but i kinda warmed to it....but...and you will read some threads about it sometimes sticking when in reverse- and mine did a few times. Was booting it on a trip down to AmD a couple years back and under throttle made a long continuous chirp a couple of times. Then after the lower than expected torque and BHP figure on the rollers i decided to change it back.
At the moment the 007p in the normal position with an open cone makes a nice sound tbh
lol the dv was 6 months old when that happened
yeah thats bang on, im running a mapped lc with yellow spring in reverse, i find the cycle time quicker ie, the dump is dropped quicker, and closed quicker since the aid of the boost on the piston makes it easier for the vac to lift the piston,
99% of turbo diverter valves on all other cars, run in what us 1.8t owners call reversed, with the boost acting on the base of the piston, i think even on a diaphragm type valve having boost act on the perimeter of the rubber diaphragm does'nt seem logical to me, plus with the forge 007 fitted the right way round the boost pressure is acting on the o-rings as well as the seal to the TIP, putting more stress on them,
ive possibly put too much thought into this, but hey im a pneumatics engineer whos usually working with 150psi +,
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lol the dv was 6 months old when that happened