Returnless style fuel pressure

Sleepin6

Silver Member
IMG_4269.jpeg Hey guys im trying to figure out how to keep my returnless style fuel pressure from dropping during datalogs
to make more power then 406hp. I have and aem 340 with the in tank regulator crushed to read 80psi koeo.
I don’t have the wiring upgraded to the itfp and am wondering if that will help at all. My last datalog is posted. Lmk what i can do to max out my returnless setup. Im running an E45 mix.
Cst5 iwg turbo, xs power manifold, jmf v2, 1050x injectors, 2.5” fmic, forged bottom end, port and bowl worked head with stock valve train.
 

Attachments

Last edited:
Do you have a datalog where fuel pressure drops? Looks reasonable to me. You have a rich area from 4500-5000 rpm that is taxing the system a bit but it's not dropping pressure to a point that I'd worry about.


T1.jpg
 
Do you have a datalog where fuel pressure drops? Looks reasonable to me. You have a rich area from 4500-5000 rpm that is taxing the system a bit but it's not dropping pressure to a point that I'd worry about.

This is what my tuner said…I can see that your PI injectors are having trouble keeping up with the fuel flow up top. The boost 28 psi is working against the rail pressure and it makes the injectors flow less and with bad atomization. A return style PI setup would be much better and provides consistent differential fuel pressure.
 
I want to max out my returnless style system before i change anything fuel wise again so im just trying to figure out if im maxed on my current setup or can push it higher with no problems.
 
I want to max out my returnless style system before i change anything fuel wise again so im just trying to figure out if im maxed on my current setup or can push it higher with no problems.
I just found out that my itfp wasn’t getting the correct voltage needed so i jumped the resistor box temporarily to see if that changes anything.
 
Newest log after fixing the voltage to the pump.


Definitely better then the first log you sent, you started leaning out at the end of your first one and in this one it’s actually staying true to target tho you are maxing out your fuel which it being in the 90s you could maybe pull some E out of the tune to bring the duty cycle down a bit, what kind of intake are you running ?

in my 6th port set up on e30 I’m making 430-450 range with 78-82% fuel duty cycle on a return less set up so ideally you should be seeing the same numbers if not more if you have an 8th port set up

I also want to run a return style configuration some day to see if any more befits would come from it but truly I’m not searching for more then 550 at most on my set up
 
Definitely better then the first log you sent, you started leaning out at the end of your first one and in this one it’s actually staying true to target tho you are maxing out your fuel which it being in the 90s you could maybe pull some E out of the tune to bring the duty cycle down a bit, what kind of intake are you running ?

in my 6th port set up on e30 I’m making 430-450 range with 78-82% fuel duty cycle on a return less set up so ideally you should be seeing the same numbers if not more if you have an 8th port set up

I also want to run a return style configuration some day to see if any more befits would come from it but truly I’m not searching for more then 550 at most on my set up
I have a jmf v2 intake with 8th port. 3.5” HTP intake.
 
Back
Top