ZO6 Fuel Pump DC

[jlbjr]

Hello,

Do you guys up your duty cycle in the very high flow areas of the tune. Stock it's already well past 100% 500-600kpa in the 425lb/hr fuel flow on the chart. I'm trying to get a little more fuel pressure at the top of WOT, E50. Could I raise the the last rows up to like 125% for 350- 500kpa? I already raised the voltage to 15.5-15.2.

2016 Z06 Auto, E50. Thanks.

[TriPinTaZ]

That wont do anything to help with fuel pressure or capacity if you don't have a low side solution. The only reason that table is modified is when you're running a DSX low side and you don't want the fuel pressure to fluctuate too much. Or if you have an entirely different fuel setup.

[jlbjr]

OK, some people are saying that raising the voltage at the FSMVoltage helps. I saw another post about raising the DC. My pressure is good in Auto shifting. But, manual all the way to redline the fuel pressure drops and PW goes up. I just need a little more.
thanks.

[Joshinator99]

OK, some people are saying that raising the voltage at the FSMVoltage helps. I saw another post about raising the DC. My pressure is good in Auto shifting. But, manual all the way to redline the fuel pressure drops and PW goes up. I just need a little more.
thanks.

The voltage is lower in LT1 cars but LT4 cars are already set at 15.5V if memory serves. If you just need a bit a more, a JMS voltage booster is the way to go.

[jlbjr]

Is the Fuel System Minimum Voltage in the ECM or CCM? Thanks.

[Joshinator99]

Is the Fuel System Minimum Voltage in the ECM or CCM? Thanks.

I believe there are tables in both that are supposed to match. In my car it was ECM and FSCM but I’m not sure if the Vettes got the FSCM or something different?

[TriPinTaZ]

The Vette's FSCM is controlled by the ECU so you would only need to flash the ECU for those changes. Increasing the voltage via the tune requires some other changes to the Alternator controls to keep the car from going into reduced charging mode(GM fuel efficiency stuff). Then commanding more pressure sooner. It helps A LITTLE. Like maybe 5-10% more E which may just be enough for some. However, I found that even then it is inconsistent because you don't always get all the voltage you want to the fuel pump.

The real solution is to install the JMS booster on the low side and then you don't have to worry about changing anything but commanded pressure and commanded pressure sooner. Then your low side will hold 75-80psi all day with no fluctuation and you will gain more headroom for E up top.

[Joshinator99]

The Vette's FSCM is controlled by the ECU so you would only need to flash the ECU for those changes. Increasing the voltage via the tune requires some other changes to the Alternator controls to keep the car from going into reduced charging mode(GM fuel efficiency stuff). Then commanding more pressure sooner. It helps A LITTLE. Like maybe 5-10% more E which may just be enough for some. However, I found that even then it is inconsistent because you don't always get all the voltage you want to the fuel pump.

The real solution is to install the JMS booster on the low side and then you don't have to worry about changing anything but commanded pressure and commanded pressure sooner. Then your low side will hold 75-80psi all day with no fluctuation and you will gain more headroom for E up top.

Yep, just do the JMS and get it over with. Unless you’re shooting for big power, in which case do the Fore triple and be done with it.

[TriPinTaZ]

I have a JMS for the C7 that was used for about 6 months. I'm selling it used now as I decided to go to the DSX low side as my fuel demands surpassed the JMS. Email me if you are interested.

[Evansa22]

The Vette's FSCM is controlled by the ECU so you would only need to flash the ECU for those changes. Increasing the voltage via the tune requires some other changes to the Alternator controls to keep the car from going into reduced charging mode(GM fuel efficiency stuff). Then commanding more pressure sooner. It helps A LITTLE. Like maybe 5-10% more E which may just be enough for some. However, I found that even then it is inconsistent because you don't always get all the voltage you want to the fuel pump.

The real solution is to install the JMS booster on the low side and then you don't have to worry about changing anything but commanded pressure and commanded pressure sooner. Then your low side will hold 75-80psi all day with no fluctuation and you will gain more headroom for E up top.

Are commanded pressure changes accessible through the ecm or do you need the credit for the fscm? 2018 zl1

[kenand1988]

Are commanded pressure changes accessible through the ecm or do you need the credit for the fscm? 2018 zl1

Ecm

[Evansa22]

Thank you!