electronic boost controller on remapped s3

[sportstractor]

its been well noted that N75's are rubbish and are slow to react therefore limiting the amount of boost that is put into the engine, especially lower down. So me and a mate are gona try an external EBC on the S3, only mod really being a rubbish remap.

only down side to this i can see is engine will lose all control of wastegate, so if not setup properly could cause damage to the engine. But if setup on the side of safety it should be fine. Anybody tried this and notied any success on S3 with standard turbo?

Upside to this is that it should be alot quicker to react than the standard control system, giving a more aggresive power delivery. Iv played with ebc's before so have no problems with it, providing i set it no higher than the ecus command pressure.

Any thought opinions/ thoughts appreciated, if theres no big difference there is no point trying it...

 

[<tuffty/>]

Couple of things to note... What do you think controls boost with an EBC? An electronic solonoid valve like the N75... You also need to be disciplined in how much boost you dial in... Too much and say goodbye to your rods...

N75 does as good job as any other solonoid... Can't see any advantage to using an EBC on a normally mapped S3. Used an Apexi on the Polo Bill built but that had 483bhp and was FWD.

Bill uses an N75 on his 600bhp Ibiza race car but has a DTA ECU rather than ME7... Still controls an N75

There are threads in other forums that suggest the use of an MBC in line with an N75 to smooth out the boost.

<tuffty/>

 

[sportstractor]

yeah an apexi was what he had lying around. Well after a read up it does seem like an improved (more aggresive) map is in order. As for a MBC, iv read that this will only reduce the spike. And MCB alone will remove softlimp option, but will carry boost higher up the rev range rather than tiling off so much. None of these options seem like a worthwhile improvement though

 

[<tuffty/>]

MBC won't carry boost higher up the rev range if the turbo can't produce it which the K04 can't... It may well hold on to more boost than the map is requesting but once the K04 is out of puff its out of puff...

Here is a bit of info about using an MBC with an N75

http://forums.audiworld.com/showthread.php?p=13285925

<tuffty/>

 

[HTC]

I love my EBC (apexi avc-r). Perfect boost every time, but then I have an AGU engine which has a tendency to provide erratic boost at best.
For you it's down to the map and not the N75. A slow reacting N75 serves for quick boost as it will open the wastegate later. So if you want more low torque you would have to swap the map's boost curve settings or like you say try an EBC. I'm sure Bill B would explain more about mapping if you asked him.

I think you understand all about not going above the maps max boost requested, but the N75 valve itself is as good as an EBC for performance.

 

[sportstractor]

yeah i know my N75 is fine, its a few weeks old. I just thought it was in its 'nature' to provide power like it does, but thinking about it, like you say, is totally controlled by ecu. My friend suggested it, but he only knows cossies really. I cant see EBC doing anything a good map wouldnt do:icon_thumright: cheers chaps

 

[badger5]

N75 is not a slow reacting solenoid at all. Its faster acting than an Apexi AVC-R one and a lot quieter to boot

Just throwing on an ebc onto a "badly mapped" car is just likelly to throw it into boost deviation mode, as the map as request boost and looks at actual via the map sensor, and deviations, be they +ve or -ve by >250mb will throw it into limp mode
MBC's take spikes out of things, and allow adjustment, but you will be confined to the limits of the "bad map" in the ecu I think

nowt wrong with N75..
I run one on my ibiza, via S60 DTA ecu, but run it via fixed duty cycles, not by request boost. AVC-R can operate the same way also.. which personally I preferred as the setting. Learn mode on request boost being as erratic as ecu asking for closed loop control on bad maps for example.

regards
bill

 

[Prawn]

would you suggest an EBC could be a good addition to an AGU lump which suffers from erratic boost Bill?

I've got an AGU which was mapped to run 22psi originally, and for some bizzare reason it now only ever peaks 16psi, there are definately no leaks. I'm not so fussed about it only peaking 16psi, but sometimes when i floor it I'll see 16psi, yet other times, I can floor it on the same stretch of road, same gear, same RPM, and it'll only see maybe 12psi, then I'll back off and floor it again and get 16.....

Kev (HTC) suffered from exactly the same problems as I did on his IHI AGU, and several other ko3s'd AGU's I've been in have suffered similar faults.

I'm really tempted to follow Kevs advice and fit an EBC, just so I can get more stable boost at levels well within the ECU's capability.