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Should realize the extra flow.
 

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HNNLIC
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It should realize the extra psi level and adjust accordingly. Unfortunately and only adjust to a certain level...hence the cut off. After this point you need to upgrade your ECU level and later on your injectors to account for the increase air.
 

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Fuel cut is a preset safety level and is not based on the fuel ratio. The stock fuel system can handle up to 280 hp.
 

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HNNLIC
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ERP said:
Fuel cut is a preset safety level and is not based on the fuel ratio. The stock fuel system can handle up to 280 hp.
In this case, why is the fuel cut level at 15.5 psi if the stock system can handle up to 280hp?
 

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It’s a good question. With a better exhaust, intercooler and software all NG900 SE could have been 230 hp stock instead of 185. But I think the idea was to over design the fuel system since the cost ratio is so small for it, with the option to create more powerful engines in the future, like the Viggen and Aero.
 

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HNNLIC
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ERP said:
It's a good question. With a better exhaust, intercooler and software all NG900 SE could have been 230 hp stock instead of 185. But I think the idea was to over design the fuel system since the cost ratio is so small for it, with the option to create more powerful engines in the future, like the Viggen and Aero.
Okay that makes since then. Thats pretty interesting.
 

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I think it´s all about margins. Even though the engine is capable of producing 280hp, not much of the rest of car stands those kind of powers for any longer time. The cars are designed to last at least 15 years reaching 300000miles with ease. 185hp or maybe 200 as in the 9-3Sport 1999, is a maximum while retaining the life span.
If SAAB had decided to go with 3" exhaust and 250hp on the ng900 and 9-3, they would have had a lot of those cars filling up the garages with warranty replacements of trannys, clutches turbos and not to forget all the badwill from people killing themselfes due to low-performance road holding.

All these things can be adressed, yes, but at a cost. Adding $5000 in aftermarket parts on a new car directly from SAAB (and by SAAB) would raise the price of a new car with a _lot_ more. And still you can´t be sure that the engine will hold for hours and hours of WOT at a 120F in some distant gulf country.

Then why did they choose those injectors? Probably due to a good deal, and that they can use the same injectors on all cars and so on, logistics is also a way to increase revenue ;)
 

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Clint, I have some Injector info I will post later. Check KevinY sight in the 9000 engine section in the meantime.

No, I have and Air/fuel and see rich conditions under full boost just like your supposed to.
 

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I agree with Tweak. Even under full bosst at max boost just below the fuel cut, the t-5 runs rich. Some have even done a resistor MAP hack raising the fuel cut by 1-2 psi and still ran rich. The t-5 system isn't as sophisticated as the t-7. You can see the results on the plugs of the t-5. Typically very sooty, whereas the t-7 plugs are cleaner. I've tried to improve on that by hacking the ground electrode, rounding it to better match the center electrode to reduce the quenching effects of the plug design. The plugs still get sooty on the metal end around the plug, but the center electrode stays much cleaner, actually bright white after 4000 miles.
 
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