Overboost?

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The way to see the boost is not through a boost gauge,but as the engine ecu see's it, so a Nanocom or similar is the way forward.More than 230Kpa is overboost as the Storm ecu see's it.
 
eightinavee said:
The way to see the boost is not through a boost gauge,but as the engine ecu see's it, so a Nanocom or similar is the way forward.More than 230Kpa is overboost as the Storm ecu see's it.
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I've got one of those Nanocoms on order since November but they're having backlog apparently and I'll have it mid January after they've got stock.
By the way, how do you tell which ECU you have? I'm hoping I have the nnn programable one, I think it's nnn isn't it?
 
eightinavee said:
The way to see the boost is not through a boost gauge,but as the engine ecu see's it, so a Nanocom or similar is the way forward.More than 230Kpa is overboost as the Storm ecu see's it.
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my boost gauge works well as well it provides me information combined with engine load gearing as well as RPMS and after a while you can become custom how the engine performs over a short period of time

considering the engines i work on i have witnessed map sensors to fall out of calibration or a temp related issue giving mixed or wrong electronic readouts ... this is why we install a mechanical boost gauge to confirm over an electronic readout.... ... depending on kind of fault chasing we are looking at ..just like going for a 2nd opinion to the doctors

the storms ecu reads pressures from the manifold a true reading sample area .this is why its best to install a the boost gauge signal line into the manifold

lost count on how many people i have met and they think they are running 230 kpa and they think this is 33 psi they forget about relative pressure
 
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RustySkull said:
Ooo blimey, well I hope this Nanocom thing arrives soon so I don't have to fanny around drilling holes for this boost guage :)
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dont forget to use the correct calculator on google when converting KPA to psi this may sound confusing but 230 kpa is 33.3586797416606 psi
relitive pressure 230 kpa = 18.662730341660602 psi
link to the calculator
https://www.convertunits.com/from/kPa/to/PSI

have a look into different BAR ratings for MAP sensors

where is with a mechanical boost gauge reads 18 psi that means its reading 18 psi its very simple
i installed mine in the manifold i removed the EGR actuators this allowed me to vacum out the debri while i drilled and tapped a fitting... you could T into the waste gate actuator line but you may find the will be a higher reading than normal this is why manufactures like to install the MAP sensor into the manifold as its more accurate sampling area

i also find with a boost gauge permanently installed i can monitor boost levels where ever i drive and conditions i drive in as well as driving style
as well as diagnose future faults and performance for example my boost gauge detected i was starting to lack a few psi over a period of time turned out i had fuel pressure issues

not many people like to install boost gauges it more of a personal choice .. but this also apply s to some dont even bother to read any pressures when tampering with a turbo and settings ....like i said its then just guess work
 
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@ozzyboydeano - The OP's question is about overboost, what is actually going on in the inlet manifold is irrelevant to the engine ecu which makes the actual decision about what the boost pressure is.What is relevant is what the map sensor tells it,if it see's more than 230Kpa it will cut fuelling - simple as that.That is what the OP needs to know right now to diagnose his issue,granted a dash full of worry gauges can be useful,but only after the thing is set up and running nicely.Then and only then can you use them as a benchmark of normal operation.
 
Well that is a tad wrong... Boost pressure is set by the actuator/boost controller the ECU reads the boost pressure from the MAP which is located in the inlet manifold so whats happening in the inlet does matter.

So running a boost gauge off the actuator will give a "good enough" reading without a nanocom or similar to read the boost the ECU is seeing. Best bet is tap it into the EGR blank for a boost gauge, which is very useful if playing with the boost!
 
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OK, let me put it another way, the only thing that matters is what the ecu "THINKS" is happening. You can ignore this all you like,but if the ecu thinks its overboosting it will cut fuelling. Yes, it is nice to see what is actually going on in terms of boost,but its all secondary to the OP's original question, especially in that this is the first time he has run it with the new non-standard turbo.So he has no idea of its characteristics when its running normally.
 
Interesting that you state 242Kpa,I never managed to get any factory SIDS for the TD5, I was only supplied with Rave discs from Omitec.I don't remember seeing any actual figures in them for max boost,maybe I never looked ! What I do remember is plenty of road testing with Testbook set up showing live data and the magic figure where fuelling was cut was 230. The refresh rate was fairly quick with Testbook,but maybe not quick enough to ever show any higher before the cut off point ?
 
Yes, unfortunately RAVE is a bit too generic in some regions like the engine management for example...also there are a few mistakes in it too
 
eightinavee said:
OK, let me put it another way, the only thing that matters is what the ecu "THINKS" is happening. You can ignore this all you like,but if the ecu thinks its overboosting it will cut fuelling. Yes, it is nice to see what is actually going on in terms of boost,but its all secondary to the OP's original question, especially in that this is the first time he has run it with the new non-standard turbo.So he has no idea of its characteristics when its running normally.
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ok for example the map sensor has falling out of callibration or the map sensor thinks its reading higher pressures than it actually is a pressure sensor can fail in many ways specially under hot conditions

wouldn't a mechanical boost gauge confirm also over a electronic read out... ps you dont need to fully install a boost gauge either for tests
these are your words below

The way to see the boost is not through a boost gauge,but as the engine ecu see's it, so a Nanocom or similar is the way forward.More than 230Kpa is overboost as the Storm ecu see's it.

so my question to you why wouldn't a boost gauge work in the OP s over boost issue... the op did also mention when he was fuel cutting.. surelly a boost gauge will detect boost creep
 
The best way to diagnose that would be a boost gauge corroborated with live MAP reading cos it can happen to have normal boost shown by the gauge while the ECU to cut fuelling as the MAP reading exceeds the overboost limit which can be due to bad MAP or AAP sensor....the gauge will only show that it's not overboost in reality it would not explain why the ECU cuts fuelling also a quite similar symptom like overboost cut off occurs if the MAF reading exceeds 680 and a boost gauge can't help with that
 
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