I've maxed out my 1650's on E85 (One Ethanol S) at the nominal 43.5psi base fuel pressure. I want to increase the base pressure to ~58psi to get more headroom. My concern is idle on gasoline as I want to be able to run gas when needed. Does anyone have any input or experience with these injectors idling at increased base pressures?

I am on a Haltech e2500 fwiw

thanks

 

I don't have any direct experience doing this, but it should be fine? Are you making the tune adjustments yourself? If so, it should be a pretty easy test?

Hopefully someone else can chime in with more direct knowledge.

 

You should be alright if you tell the Haltech that the base fuel pressure is changing to 58 psi. I only have experience with AEM ECUs, but there is an option to have the software automatically rescale the fuel map when changing the base fuel pressure. It never got it exactly right, but close enough that only some small, fine tuning adjustments were necessary to get AFRs back to where they were prior to the change.

 

1650's and 2000's idle better with higher base pressure.

 

Update,

Bumping the fuel pressure from 43.5psi to 58 psi base pressure reduced my IDC's from 103% to 90% at 8k rpm and 30psi boost 11.7 AFR.

This did require some tuning of the VE table, where the increased fuel pressure dropped the VE ~5-10%. I'm thinking the 43.5psi data from FIC may have been a little off as the reduction was bringing the VE's closer to 100.

now to run the E85 out and put in 93 and see if i can get a respectable afr at idle....

Update: The car is able to idle at 14.7 with ~51 psi rail pressure with an ethanol content around 15%. Good times.