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You'll find that the stock ECU starts to struggle long before the turbo itself is in danger (it will run to 14psi plus....probably....)

The stagea ECU is very conservative and will quickly run very rich and reduce the timing; you will notice this as more boost not making it go faster....and lots of black smoke.

So....if you want to run more than about 12psi you are going to have to do something electronic anyway (eg new computer or SAFC or fuel cut defender)

Here's 2 graphs from my car in the old days.....red line is stock (top line is power, dotted line is boost). black line is after installing a fuel cut defender.

stagea_dyno_boost.jpg

This graph shows why the power goes down like crazy; the stock computer was dumping in heaps of fuel (running rich) to protect the engine from what it assumed was an issue....see dotted red line which is the air/fuel ratio on the stock computer.

stagea_dyno_afr.jpg

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Where did you hear that info? Your Mum.

Why do you doubtimg it? Your Mum talks some shit.

Are you new to the internet? No, unfortunately I'm not. I do however see as to how you may have been confused regarding my prowess. Given I joined a topical forum, located the relevant Stagea discussion pages and I tried to make a general inquiry about said stagea like a tots newb. lol ;) #twat

Your not the first to raise the boost on a stock turbo. & I wouldn't be the first in given ya Mum some pounds per square inch either. (Tip: that's like a quite a lot, more than 3 bars even).

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You'll find that the stock ECU starts to struggle long before the turbo itself is in danger (it will run to 14psi plus....probably....)

The stagea ECU is very conservative and will quickly run very rich and reduce the timing; you will notice this as more boost not making it go faster....and lots of black smoke.

So....if you want to run more than about 12psi you are going to have to do something electronic anyway (eg new computer or SAFC or fuel cut defender)

Here's 2 graphs from my car in the old days.....red line is stock (top line is power, dotted line is boost). black line is after installing a fuel cut defender.

stagea_dyno_boost.jpg

This graph shows why the power goes down like crazy; the stock computer was dumping in heaps of fuel (running rich) to protect the engine from what it assumed was an issue....see dotted red line which is the air/fuel ratio on the stock computer.

stagea_dyno_afr.jpg

Thanks mate for your helpful response, I noticed that the modest increase I gave it didn't necessarily equal the expected returns. Can see why this may be the case now.

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I like the way you say you aren't new to the net but failed a quote edit.

Anyway, as Duncan kindly provided, and you figured out, just raising the boost on a stock ecu really isn't goiin to provide fantastic results.. As has been mentioned numerous times before.

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The stagea ECU is very conservative and will quickly run very rich and reduce the timing; you will notice this as more boost not making it go faster....and lots of black smoke.

So....if you want to run more than about 12 psi you are going to have to do something electronic anyway (eg new computer or SAFC or fuel cut defender)

Had another look at your graphs and finding it a little odd that the fuel seems to drop so drastically (pre FCD) on basically the comparatively stock perimeters. While the Blue line is displaying a more even and greater power curve the two PSIs remain pretty equal. I would have assumed that at around normal performance the ECU/Injectors should be able to maintain load?

While I am not noticing any black smoke running at 10 psi, you mentioned that this may be because of the ecu retarding the timing & loading extra fuel, leading to injector failure. Wouldn't this extra fuel mean that it would be capable of simply providing the extra requirement? or is that the injectors are not able to maintain that load and essentially fail?

Is there any short term benefit to insure the exhaust flow is in turn increased, dump-Cat-mani-exhaust etc? Otherwise it appears that a ECU tune is really the best option.

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Yep that's exactly the point....the stock stagea ECU is very conservative and does not like extra boost. FCD was a cheap and dirty fix, something like an SAFC would be a better idea for a car that is going to stay reasonably standard. Whole ECU replacement is a couple of grand no matter how you go about it.

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