N75 upgrade

Arrkon

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Can just replacing the n75 increase boost pressure? If so, what part no is best and what benefits?(more hp?)

Car is a 2000 1.8T AGU A4,

Thanks guys
 
Have a look at the ecs tuning one that's on eBay search n75 1.8t race valve here the description they give


The N75 is the VW/Audi part identification number for the wastegate by-pass regulator valve. This valve is responsible for controlling the movement of the pneumatic actuator which drives the wastegate. The wastegate is an internal valve in the turbo-charger which controls the amount of exhaust gas that flows over the turbo impeller generating boost.

Under normal operating conditions the engine's ECU sends signals to the N75 valve asking it to open or close which adds or reduces pressure on the wastegate actuator which results in more or less boost. The ECS RACE N75 valve modifies the normal operating parameters of the original N75 valve by delaying the speed at which these ECU signals are interpreted.

The result is a higher initial peak boost and an elevated boost curve which tapers back to stock/chipped levels over the engines rev range. Average boost gains are 1-3psi over the rev band.
 
yeah spotted them, would fitting one from a 190PS 1.8T or even the 225PS TT engine do anything???
 
You need the N75J valve from an audi RS2, Spikes higher and holds boost longer.
 
They also cause it to go into limp mode...

As i understood it, the "H" variant causes limp, whereas the J doesnt?

You can just adjust your existing N75 valve to make it come on boost harder. Free to do, well... as long as you don't break it.

How can that be done?
 
TBH i wouldnt bother. All it does is give a useless and dangerous huge spike of boost when the turbo first spools up. The J valve has also been shown by Welly on here to allow the boost to tail off earlier, presumably as a result of the ECU trying to control the massive spike and pulling back the N75 duty cycle.
 
TBH i wouldnt bother. All it does is give a useless and dangerous huge spike of boost when the turbo first spools up. The J valve has also been shown by Welly on here to allow the boost to tail off earlier, presumably as a result of the ECU trying to control the massive spike and pulling back the N75 duty cycle.

ok, Just trying to come up with some cheap performance enhancing mods :D
 
The cars ECU is pretty sophisticated, and doesnt really take well to trying to fool it into doing things it shouldnt be doing.

If this is a late car, then it has a boost sensor, so any fiddling with the boost is likely to see it drop into limp mode every time you stick the foot down. You can get away with a little bit more on the earlier cars, but that doesnt mean its a good idea either.

You need to remap the ECU if you want more power, i've seen companies advertising remaps starting from £100.
 
£100 for a remap??? cheapest i've found is £200-250

at 100 notes, its very tempting
 
Beware the £100 map................ :no:

I myself personally have never had the experience of one but I have heard too many horror stories of el cheapo maps in the past during my Volvo T5 days.

Same as always, buyer beware. If it seems too good to be true, then it invariably is..... :banghead:
 
Just be careful when you play with N75 last time I was in MRC and my car was putting 600Nm Torque because of faulty N75 and the guys at MRC told me to change it as soon as possible as I could blow up the turbo's...
 
Was a company advertising postal remaps on ebay for £100.

Sure its a risk buying a cheap map like that, but tbh they've probably just knocked off some other tuners maps anyway.
 

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