I was just going to post that when Randy's car made this power last night it was actually more like E98 than E85, and it also has a 92K old filter. I would like to suspend my judgement of flow characteristics. I cant remember if we punched the pump on his car or not either.

So in my mind the jury is still out, and i will defer to Mychailo

aaron

 

AHH Jesus... decisions, decisions...

 

That's me. I'm at 85-86% duty cycle at 25# which is right at 500whp. This Is with an unmodded walbro and stock FPR and Fic 1050s.

27# puts me right at 90% duty cycle.

 

reviving an old thread....but have you considered a fuel rail? The stock one has very small openings.

Just a thought.

Also, you could try routing a vacuum line directly from the intake mani to the fuel pressure regulator as a way to have rising rate fuel pressure. Some have said that the stock fuel pressure solenoid is only for startup....so I am not sure this will help.

 

I had an inline Bosch and a walbro 255 and the problem is that if you don't run the inline pump full time, the walbro will eventually burn out (1-2 years). If you run it full time then your idle will be craptastic. That setup was good enough for around 550whp though.

I just switched to a double in tank setup, using the evap line as a second fuel line and I gained 18% headroom over my old inline setup. I am on 1150cc FICs. I can hit 530whp now at only 80% duty cycle. I could probably hit 600whp before running out of injector now.