Different N75s, tuning potential or snake oil?

[Animal Mother]

Can fitting different N75s have an effect on the car?

A few forum discussions on the web on this matter, like this.

Is it just snake oil or is there something in it?

If there is something in it, why and how? I thought N75 was basically a pneumatic solenoid switch.

[Rocco]

wich is the best n75 for our S2??? i heard about the 3b have a diferent n75 and the ABY and ADU have the same n75 but other diferent..its ok'''?? wich is the best?

[urquattro-island]

i

have the one from audi tt 225hp, works a treat.

[jameswkr]

ABY and 3b N75s are different part numbers because the electrical connector is rotated. See forums.audiworld.com/s4s6/msgs/49283.phtml for a semi technical review of the differences between the various types available......

[Animal Mother]

People seem to be claiming differences in performance. I can't see how this is possible.
Is it possible or is it just the psychosomatic effect on the drive, like washing your car is!

[Fat Audi 80]

Probably is better when you fit a new one. I found that my boost held on a little longer and the car felt a little "snappier" after changing it....

Placebo effect too no doubt.

[hiltoa]

Different (but similar enough) kettle of fish, but when I fitted an N75J (as fitted to ABY) to my 1.8T the engine definately boosted more aggressively for the first few hundred miles (I have a boost gauge) but the ECU has adjusted to overide 'most' of the boost naughtiness now.
I would have to bung my old N75 back on to see for sure what goes on, but until I'm ready to throw the car at MRC for a remap, I can't be ****d.

[S2central.net]

This is snake oil and placebo effect...

As stated these valves are generally just different to accomodate variations in connector & pipe positions.

Any N75 that can modulate as fast as the ECU requires it is a good one.

N75 valves obviously slow down a lil and degrade with age so it would be easy to 'feel' a benefit from say swapping a tired old ABY one with a brand new TT one. No ****...

Paul

[s2driveruk]

side issue but given it is open to plenty of heat cycling, is there any benefit in wrapping it in something to reduce heat soak/ageing?

[S2central.net]

Good point... couldn't hurt... but might look a bit pants is all...

[4WheelDrifter]

Different (but similar enough) kettle of fish, but when I fitted an N75J (as fitted to ABY) to my 1.8T the engine definately boosted more aggressively for the first few hundred miles (I have a boost gauge) but the ECU has adjusted to overide 'most' of the boost naughtiness now.
I would have to bung my old N75 back on to see for sure what goes on, but until I'm ready to throw the car at MRC for a remap, I can't be ****d.

I stuck the old 3B N75 on the A3 and the boost was savage. It made it pretty tricky pulling away in 1st and 2nd gear, and eventually went into limp home mode. So I put it back the way Mihnea intended, 1.4 bar is enough for everyday use anyway.

I've not tried the A3 N75 on the S2 though, maybe I'll slip one onto Bo's car, and see if he notices.