Mapping S2,Boost limit

[AquaS2]

The Phirm have a fair few b5 rs4's going there, but not heard of them using any of the older stuff.

[jeffstoo]

Hi Piotr
My car is basically the same spec as yours apart from it being a 3B still on a dizzy. I too had it mapped by Mark who I found to be straight up honest guy who takes pride in his work.
My car has been running 1.7 bar of boost using only the wastegate spring for the last 4000 miles without any problems. I am by no means an expert but here are my thoughts..... I know a lot of people don't like running without the N75 but for me it simplified the way system works and will make any future running issues easier to diagnose for me as a diyer. As I see it the N75 is a safety device for engine preservation and I assume it can also be used for fine tuning boost against fuel / timing when mapping, ultimately I can't see it having any effect on how fast / hard the turbo spools. There are a lot of high powered cars out there running only springs.

I think as Alex has said that if the N75 is disabled the ECU no longer controls boost as its done by spring pressure. I assume therefore that the boost chip is no longer a player in the game.
If your car was going ok for 50 miles after the mapping I would assume that Mark has done his job right. As Newsh, I have been plagued with boost / fuel cut problems in the past, changed MAF, cleaned contacts in situ, used copious amounts of contact cleaner, problem wasn't resolved until I renewed contacts in plug. I think I would be looking for something MAF / wiring related.

If I was getting 360 hp I think I would be happy with that, at least you know it's a safe 360 and if you have a AFR gauge keep an eye on that and all should be good. I know we all want that little bit extra but I think it will cost you a lot of time and money chasing another 20hp, also as we all know when you have 380 you need 400 and on it goes.
I have probably talked a load of old rubbish and not helped diagnose your problem but it all makes sense in my world.

[piotr]

Hi Piotr
My car is basically the same spec as yours apart from it being a 3B still on a dizzy. I too had it mapped by Mark who I found to be straight up honest guy who takes pride in his work.
My car has been running 1.7 bar of boost using only the wastegate spring for the last 4000 miles without any problems. I am by no means an expert but here are my thoughts..... I know a lot of people don't like running without the N75 but for me it simplified the way system works and will make any future running issues easier to diagnose for me as a diyer. As I see it the N75 is a safety device for engine preservation and I assume it can also be used for fine tuning boost against fuel / timing when mapping, ultimately I can't see it having any effect on how fast / hard the turbo spools. There are a lot of high powered cars out there running only springs.

I think as Alex has said that if the N75 is disabled the ECU no longer controls boost as its done by spring pressure. I assume therefore that the boost chip is no longer a player in the game.
If your car was going ok for 50 miles after the mapping I would assume that Mark has done his job right. As Newsh, I have been plagued with boost / fuel cut problems in the past, changed MAF, cleaned contacts in situ, used copious amounts of contact cleaner, problem wasn't resolved until I renewed contacts in plug. I think I would be looking for something MAF / wiring related.

If I was getting 360 hp I think I would be happy with that, at least you know it's a safe 360 and if you have a AFR gauge keep an eye on that and all should be good. I know we all want that little bit extra but I think it will cost you a lot of time and money chasing another 20hp, also as we all know when you have 380 you need 400 and on it goes.
I have probably talked a load of old rubbish and not helped diagnose your problem but it all makes sense in my world.

No ,absolutely no rubbish in what you are saying And every opinion is good for discussion.
just to clarify,my car was ok for 50 miles after the job was done because I was driving on twisty slow roads and my Mrs was working as a boost limiter
it's start happening as soon as I went on the motorway ,first time I have put the foot down it did this straight away .Like I said few times already I also think Mark is a lovely chap and honest as well so I believe we will get to the bottom of it together with no issues .

In regards to what you are saying boys about ECU not controlling boost/fuel ?? Cut anymore ...
it was Mark who show me on the screen that he is changing the figures to 255 that means nothing to me but he said it's the highest he can put in there but this made no change at all.
surely he should say that it's no point changing anything as ECU is not seeing/controling this anymore ???

[rxl]

Sounds interesting but not having safety in the ecu will kill an engine if something is wrong. If your not limiting boost and ignoring all the issues like Maf readings that are bad is not the best idea.. I think using a chipset like from prj with safety imiters will save some money in engine rebuild.

[twoqu]

What has been proved is that a generic chipset on the same level of boost out performed the bespoke map. So if you were having a suit made by a tailor you would expect it to fit better than one of the peg!
Not sure what spec John's ecu is but it would have been interesting to see what it could have done if the N75 was reconnected and the spring put back to stock. If it didn't knock and the afr was reasonable then clearly you could have done worse than duplicate that. Probably cheaper too and more convenient.
The value of 255 is the max that can be entered I think. Not sure what map he was altering but the previous statements appear to relate more to the load side.
It does seem that he prefers to map on the spring or use a boost controller rather than the N75. Can't remember the pro's of this. The con's have been discussed.
As I have said previously this issue sems to be related to using a stock ABY ecu rather than either a modified one or indeed a genuine RS2 one. I am assuming he used the ABY sw rather than the RS2 sw which of course needs that pesky resistor change which is related to maf range. The map sensor range has been discussed previously.
So Motronic options are either a modified ecu plus generic chipset, or become a pioneer in PRJmod, still needs ecu mods although not that resistor. I guess the costs associated with this could be reduced if the Forum somehow funded the necessary equipment to perform this task. Indeed members might have some of the tools laying around idle or could offer to do one part or other of the process. Of course that leaves the actual mapping procedure to master for our particular vehicles rather than vague ideas picked up from the usual sources. I guess that would fall into the category of spoon feeding!

[LHD_Kid]

I'm reading this with equal amounts of interest and dismay... I was planning to see Mark for mapping myself soon.......

I also have eboost2 and 4 port solenoid.... now I'm wondering what I should do........

[Costash]

I'm reading this with equal amounts of interest and dismay... I was planning to see Mark for mapping myself soon.......

I also have eboost2 and 4 port solenoid.... now I'm wondering what I should do........

Aftermarket ecu is the way .least two options using oem loom is no brainer...

[piotr]

I'm reading this with equal amounts of interest and dismay... I was planning to see Mark for mapping myself soon.......

I also have eboost2 and 4 port solenoid.... now I'm wondering what I should do........

Hi buddy.
You should go to Mark and make your own opinion. Don't let my problem influence your decision.
As you can see there is alot of people who have had cars mapped by Mark and they are happy.

[piotr]

And just to clarify boys ,as some of you mentioned about chasing the extra 20bhp.
this is not what I'm after ,I'm not chasing extra BHP,What I'm after is getting to the bottom of what the issue is that going over 1.3 bar is impossible .
if the car would be boosting like some of you mentioned to 1.7-1.8 bar and would produce 350bhp for example I would be more then happy.but the fact that I can't get that level of boost that other people have got from the same setup really bugs me .

[twoqu]

When it was cutting out what was the code? That might help narrow it down. Seem to remember that a certain person said a fuel cut always leaves a code!

https://www.s2forum.com/forum/techni...light=fuel+cut

[piotr]

When it was cutting out what was the code? That might help narrow it down. Seem to remember that a certain person said a fuel cut always leaves a code!

https://www.s2forum.com/forum/techni...light=fuel+cut

No dtc-s stored at all (apart from usual when engine not running )

[LHD_Kid]

post #28 of your link...

Most likely the ECU clicks as well during this.
Any "fuel cut" software wise will have a "Maximum boost pressure exceeded" code logged.

If there is no such code, it's not fuel cut. End of.

[LHD_Kid]

Aftermarket ecu is the way .least two options using oem loom is no brainer...

Sure... but then, I still need to find someone to map it. I still need to purchase the ECU... it really isn't a no brainer if there is a sensible option for a one-off mapping of the existing motronic...

[piotr]

Sure... but then, I still need to find someone to map it. I still need to purchase the ECU... it really isn't a no brainer if there is a sensible option for a one-off mapping of the existing motronic...

I start to think that if you not going for some crazy power and you don't care about things like lounch control ,anti lag it's no point to spend alot of money to buy aftermarket ecu and then spend money again to map it .if you can get somebody good who can tune your existing ecu I would stick with OE - at least this is what I'm going to do for now

[audiman]

Running just on a huge spring is a horrid way of mapping these cars. They drive crappy and laggy. It sounds like you are hitting MAF limit. It should be disabled in your software. You also can’t run 1.9 bar boost on a stock MAP sensor that only reads to a max of 1.5 bar of boost.