N75 J Valve
The N75 J from that I got from Potterman
The other side of the N75J
The N75J is part of the system that determines how much boost is held by the diverter valve. Often when you add a chip to a 1.8t powered VW, the increased boost needs a little more control to be smooth. The N75J not only lets the boost peak a little higher, but it also helps get rid of surging.
I did this mod in conjunction with bypassing the N249 valve at the front of th emotor. That is another way to get rid of surging that comes from the higher boost levels that you get with an aftermarket chip. My surging wasn't bad, but I did notice that the boost is much smoother with these mods. You can read more about bypassing the N249 on VW Vortex.
The N75 valve is located at the upper part of this photo towards the right. It is underneath the boost tube for my intercooler. I disconnected the intercooler hose to make it easier to get to the N75 valve.
Here is the N75, right next to the diverter valve. The bottom clamp is reusable. Grab it with a pair of pliers and the N75 comes right up.
The old N75 is removed. You can see the re-usable clamp.
Here is the OEM N75 still hooked to two of the boost hoses next to the N75J that I'm about to install. Cut the old hose clamps off the OEM N75 valve. I used a dremmel and it worked pretty well. These are not reusable. You'll need to get some new hose clamps. I used small ones for fuel lines because they don't chew up the vacuum hoses. You'll notice one difference with the N75J valve. The plug for the wiring harness is on the other side. The OEM harness reaches just fine, just make sure that you insert the long tube down into the intake tube.
The installed N75J. Compare this to the photo near the top and you can see that the wiring harness is on the other side.