no FPR injectors and fuel pump needed when boosting 8 psi

Forced induction, NA tunning, exhaust, just performance

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AntDX316
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no FPR injectors and fuel pump needed when boosting 8 psi

Post by AntDX316 »

http://www.frontiernet.net/~dbipes/hipsifuel.htm

"By my measurements, in a warmed-up stock engine at idle the injectors are on about 10% of the time, and at WOT about 50%."

"I have monitored both fuel pressure and air/fuel ratio under sustained boost. My stock pump is capable of sustaining 80+ psi and, because the mixture stays rich, sufficient fuel flow. The resistor mod allows me to maintain fuel pressure well below 100 psi and not require an auxiliary pump."
Pir0
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Post by Pir0 »

'Increasing the boost from the standard 6 psi to 8 psi requires that the fuel supply under boost also be increased. There is more than one way to do this. My solution involves tricking the engine computer into delivering the extra fuel when needed.'

You missed one bit. He's already got a turbo'd engine.

The reason a lot of ppl go for upgraded fpr and injectors when running boost at about 8psi, is because they're turbo'ing an engine with which wasnt turbo'd beforehand, and running it on standard engine management.

So, the reason he didnt need to change that was, because they're already an upgrade from standard n/a items. The injectors, fpr, and pump are already rated for higher power. Whereas on an n/a engine, it's just thinking you're driving into an 8psi strong wind constnatly when on boost. The injectors werent rated for that, and the ecu doesnt know how to cope with it over a certain limit.
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exist3nce
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Post by exist3nce »

Good post Pir0..... I agree

That motor was already boosted. Thats a big difference from going NA -> Turbo.
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AntDX316
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Post by AntDX316 »

his car is a mazda miata that car isnt turboed stock

alot of people can do 5psi without any fuel mods but would 5-6 be a huge difference?

i was pressing in my 6psi wastegate and it was really hard to push in
Nubira2.2
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Post by Nubira2.2 »

a FMU is cheaper than a new engine
so atleast i would get that
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Mitsubishi Eclipse GST 304whp 319tq @22psi w EVO 3 16G Daily Driven
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