220 injectors e85 fuel pressure issue

[IATurboBuick]

I can't seem to get the idle fuel pressure low enough. After I drive, it will come down, but any throttle input at all raises it back to the 60-70psi idle range.

I changed regulators and have not seen any issues with the return line. Anyone have some expeience with this same issue?

 

[GNVYUS 1]

What do you mean by after you drive, like turn it off?

Idle pressure being jacked up is usually the combo of fuel pump volume and return line size. Sometimes the factory and aftermarket style rail regulators are too small an orifice for certain volumes.

What fuel pump or pumps?
What fuel regulator model #?
Factory return line or an size?

If you're on 220lb injectors and using the factory return line with say a dual pump, you might've read too many posts from the OEM purists that the factory return like is plenty and kept it. 6an minimum return line and if you're dual pumps 100% always on probably 8an minimum.

 

[IATurboBuick]

What do you mean by after you drive, like turn it off?

Idle pressure being jacked up is usually the combo of fuel pump volume and return line size. Sometimes the factory and aftermarket style rail regulators are too small an orifice for certain volumes.

What fuel pump or pumps?
What fuel regulator model #?
Factory return line or an size?

If you're on 220lb injectors and using the factory return line with say a dual pump, you might've read too many posts from the OEM purists that the factory return like is plenty and kept it. 6an minimum return line and if you're dual pumps 100% always on probably 8an minimum.

I did a poor job explaining. This is a racetronix line setup, reg, 550 hellcat. I have this feelig that the -6 return is too small. When you start the car it idles at 70PSI, but as you drive it, it slowly comes down to normal pressure, but excaltes quickly when you pick the gas back up driving it.

 

[GNVYUS 1]

What Regulator?

This sounds like the rail regulators that even though the return is 6an, the orifice on the rail isn't large enough or internally choked etc.

 

[IATurboBuick]

its a racetronix. i guess im not sure what to do about the potential issue you identified. its a stock rail.

 

[GNVYUS 1]

Take a picture of the reg on the rail and link to it on their website.

You might need to go to an external regulator like Aeromotive or Fuelab that has a much larger external and internal cavity for fuel volume.

 

[Mr.Spool]

its a racetronix. i guess im not sure what to do about the potential issue you identified. its a stock rail.

Your using a stock rail with 220lb injectors and a single hellcat pump?

 

[IATurboBuick]

Your using a stock rail with 220lb injectors and a single hellcat pump?

correct.

 

[Mr.Spool]

I have this feelig that the -6 return is too small.

Nope

 

[Mr.Spool]

correct.

With 220 injectors (which is very large on these motors)The rail should be upgraded and duel fed for -8 /-6 line setup as well and external regulator from aeromotive along with the proper pump or pumps.
This is to properly feed the 220lb injectors and it also maintains a cushion on the injector if you push the power