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Hey guys, had my car on a dyno the other week for a power run, they put a sensor in the exhaust etc etc, I dont know much about dyno's.

On the print out the AFR;s reached just above 15 on full boost. I have been told that this is a sign of a dieing fuel pump. however im wondering, is the fuel pump internal or external as i would rather replace it with something better then the factory pump.

Will a bosch fuel pump work? something along the lines of a 040. If so what is the part number?

Do i need to alter any of the existing fuel lines, fuel pressure etc?

Any help will be greatly appreciated.

The car is a S1 R33 gtst.

Made 240 hp atw running not tip top.

At a certain point the power curve went horizantal and then back up again. As this happened a big black cloud of un burnt fuel came out. then it shows that its running lean at 15 (afr's)

Help guys!

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Hey guys, had my car on a dyno the other week for a power run, they put a sensor in the exhaust etc etc, I dont know much about dyno's.

On the print out the AFR;s reached just above 15 on full boost. I have been told that this is a sign of a dieing fuel pump. however im wondering, is the fuel pump internal or external as i would rather replace it with something better then the factory pump.

Will a bosch fuel pump work? something along the lines of a 040. If so what is the part number?

Do i need to alter any of the existing fuel lines, fuel pressure etc?

Any help will be greatly appreciated.

The car is a S1 R33 gtst.

Made 240 hp atw running not tip top.

At a certain point the power curve went horizantal and then back up again. As this happened a big black cloud of un burnt fuel came out. then it shows that its running lean at 15 (afr's)

Help guys!

I'm not a pro myself in dyno read outs, but you can get fuel pumps that r just a direct swap to your stock 1, nismo is the best out there, n alot of people use bosch as well. Replacing your stock to like a nismo fuel pump for example is enough up to about 350 KW so u looking at about 470 HP

I would test the fuel pressure first.

Could be blocked fuel filter, crook fuel reg, dirty injectors, pump is the last thing really.

If you do go down the track of a new pump the 040 is the most direct fitting pump for your car, without spending megabucks on a Nismo.

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