I have intake, DP, MP, CB, and intercooler soon. The PFC is showing about 86.5% duty cycle on the injectors and I'm boosting at 13-14psi. Do I need to upgrade my fuel pump and which one is the cheapest and most effective? Thanks

 

Shoot! I'm hitting 99.8% on my inj duty cycle now. I think I'm gonna burn out my injectors. Does upgrading the fuel pump take care of this or do I need bigger injectors?

 

list all mods.

luigi

 

you need bigger injectors and a better fuel pump. if you have a powerFC get 1200cc secondaries or take yours out and send them to www.rceng.com . you will burn out the injectors soon. turn down the boost for now.

 

Upgrading the fuel pump will have absolutely zero effect on the duty cycle. The ECU does not know about fuel pressure, and that is the only thing that can change when you upgrade the pump (well, O2 reading too, but the ECU doesn't care on boost). You just need "enough" pump to maintain pressure at high boost and high RPM (when pressure and flow are greatest). If you don't have enough pump, the pressure will drop and your car will be inconsistent (e.g. pressure will drop more with the radio blasting, etc.) and lean (if your car is tuned right and not running really rich otherwise).

You might be able to reprogram your fuel map to take advantage of the available fuel pressure you have after a pump upgrade, though. If your car hits 99% because it was programmed to run okay when the pressure drops, you might be able to lower your duty cycle because the pressure stays where it is supposed to be. But it won't do this on its own -- you'll have to change the settings.

At 13-14 psi you need a bigger pump. Denso, Walbro, and Bosch are all good pumps for your needs.

I've got a fuel calculator that can help you choose a pump:
http://www.maxcooper.com/rx7/how-to/...tem/calcs.html

-Max

 

I have

Intake DP, MP, CB, and Power FC.