Motronic Mapping N75 or Manual Boost?

[prj]

I can name you one that's unreliable...

I'm not disputing how good the N75 motronic system is but its certainly not the most reliable. I have replaced seven in my ownership of high powered Audi's and the majority have produced boost spikes when shoot.

What exactly is unreliable?
The N75 valve?

[cooperquattro]

i am not even going there with this one!
its obvious from other posts that you have to have the final say,
for my aplication motronic is useless
standalone ecu and standalone boost control has far more scope for me over motronic..

[DJones]

What exactly is unreliable?
The N75 valve?

Yes the valve (touch wood) never had motronic issues but the valve have driven me to despair...

I had a brand new B5 RS4 and the valve lasted 300 miles. To be fair the replacement lasted 5k and so it went on.. my current B5 has had three so far.. none ever messed with just fitted and used..

[prj]

i am not even going there with this one!
its obvious from other posts that you have to have the final say,
for my aplication motronic is useless
standalone ecu and standalone boost control has far more scope for me over motronic..

Standalone ECU is something completely different from just a standalone EBC used with the stock system, which is the topic of discussion here.
The thing is that in Motronic the boost chip is what controls knock. If you leave that untouched, you'll hit a brick wall at a certain point. That's all I am going to say.

Yes the valve (touch wood) never had motronic issues but the valve have driven me to despair...

I had a brand new B5 RS4 and the valve lasted 300 miles. To be fair the replacement lasted 5k and so it went on.. my current B5 has had three so far.. none ever messed with just fitted and used..

You don't have to use the N75 solenoid if you don't like. You can use most pneumatic valves as long as you map the ECU correctly...

[DJones]

Standalone ECU is something completely different from just a standalone EBC used with the stock system, which is the topic of discussion here.
The thing is that in Motronic the boost chip is what controls knock. If you leave that untouched, you'll hit a brick wall at a certain point. That's all I am going to say.


You don't have to use the N75 solenoid if you don't like. You can use most pneumatic valves as long as you map the ECU correctly...

To be fair PRJ that's my point you can, most cant, for you the standard system is best (and I'm not disputing its ability) but for me its not.

[prj]

To be fair PRJ that's my point you can, most cant, for you the standard system is best (and I'm not disputing its ability) but for me its not.

I see your point, but I am afraid it'll always be this way with Bosch OEM systems, since everything is kept secret.
If you look at Subarus, EVOs and Hondas it's a whole different world. Too bad it can't be the same for Bosch systems.

[A80Avant]

I believe that it is best to map with the N75 valve(of a better quality) unless you want different boost profiles in a switch for example.

If you have the map done by a tuner, so that you have the correct fueling maps to the boost you go to, then you can take the motronic off controlling boost and get a EBC that you can manipulate to your desire.
Yes you will loose the ability your motronic to limit boost on various circomstances some of which devastating for the engine, but if it is that your cambelt will slip, or your knock sensor will fail, then believe me the limiting of the boost wont save you. A lot of engines have failed like that and they werent even ON boost! So yes motronic has the ability to save you from various things, better to have it than not have it at all. It doesnt 'see' every engine problem though. My motronic was not 'hearing' knock(due to aggressive timing) on newly inserted knock sensors on my previous setup and did not limit any boost or drop me to safe mode, but i did hear it from the driving seat!
If you want though to have different boost profiles and play around, do a valet mode or something, then you will need an EBC for that at least.

[prj]

You can have different profiles on a switch using Motronic.
Paul has been offering that for years.

[A80Avant]

sure, but that again is a one off. Not tweakable by the user.

[prj]

sure, but that again is a one off. Not tweakable by the user.

This whole "tweakable by the user" thing is funny anyway.
I guess it depends on the user - if you are the obsessive compulsive type where you need to change everything every second, then you should not be running an ECU you can't tune.
Running standalone EBC's with Motronic isn't a good idea anyway - switch to a standalone instead of doing it half-assed.

[A80Avant]

oh dear... not again...

i wont be the one to spoil this thread this time. I gave my opinion. Any more and it will become boring once again.

Hope i helped a bit Gus.

cheers