HP calculation for less than E85

[Flyin Brian]

I have been looking at the hp calculations for E85 but how would I estimate hp for the crappy E65 I have been getting at the pump here in Houston? I don't have any new track times since I switched to E85 so I don't know my current trap speed. I got the tune closer now but am out of injector. Did a street run and am lean (12.8:1) at 87% dc and 5500 RPM with 24 psi boost on 80 lb injectors and a base FP of about 43 psi. I think I can turn up the base FP and increase the WOT fuel and get to a reasonable AFR at 24 psi boost but will have to go to 120's to crank up the turbo to 28 psi where it wants to be. Just wondering what my approximate hp is at 24 psi maxing out the 80 lb injectors with E65 fuel. Hope to go to the track in the next few months when I get new drag radials. Thanks.

 

[Rafs-T-Type]

I'm maxing out 120 lber's, but there is no way I am at the HP required to do so. Just because you are maxing injectors, it doesn't mean you HP can be calculated from it. Also your tune is jacked if you went 12.8:1 @ 87% IDC....well not necessarily the tune....your pump may be laying down, you may have a clogged fuel filter, a bad FP regulator...or something else. I certainly would not jack the boost up until my AFR's looked a little better....granted I don't think 12.8 is too far off base.

 

[Flyin Brian]

Any idea what kind of power you are making maxing out 120's? I don't think I have a fuel supply problem at this level? Dual in-tanks with -8 feed. No pressure fluctuation at WOT on mechanical gauge and logged FP always shows a 1:1 rise with boost. Fuel filter is a just a 100 micron screen. I know I should go external pump but it is not in the budget this year. I need to go to the track and see what it traps at.

 

[Rafs-T-Type]

Any idea what kind of power you are making maxing out 120's? I don't think I have a fuel supply problem at this level? Dual in-tanks with -8 feed. No pressure fluctuation at WOT on mechanical gauge and logged FP always shows a 1:1 rise with boost. Fuel filter is a just a 100 micron screen. I know I should go external pump but it is not in the budget this year. I need to go to the track and see what it traps at.

HP level is most likely not anything good. Anything I have to say would be a guess. It's a puzzle I have yet to figure out. I don't see a reason to need an external when internals are getting the job done.

 

[Chuck Leeper]

Run the injs at the LS fuel psi. @60#, those 80's become 94's.
Also, do you have the filter socks on the pumps? Are they 340's, or 255?
If no filter socks, and a 100M inline, you may be seeing exactly what I posted about.

 

[Flyin Brian]

I have run the base FP as high as 55 psi with no problems other than it is hard to get the idle and part throttle lean enough. I have the SD chip but am not running it in wideband mode right now. I have the Racetronix dual in tank 255's with the filter socks on and the -8 feed with -6 return. I also have the Racetronix heavy duty wiring and relay kit and I am also running a volt booster. 16 volts at WOT. No elbows in the feed. Line runs all the way down the passenger side frame rail and curves up through the engine compartment to the -8 fitting on the fuel rail. Fuel rail was modified for the -8 fitting correctly so the ID at the fitting is big. In-line filter is a straight through Jegs -8 in -8 out with the 100 micron stainless screen. If I am getting E65 instead of E85 that means more gasoline and less ethanol so at a given flow rate of fuel theoretically I am making more hp with E65 than E85???? Car seems to run like a bat out of hell right now.