Stock VFR Fuel Injector Rating?

After scanning the archives (bad Boolean juju maybe) and the service manual
and not finding the information, hopefully somebody will know this.



What is the stock rating of the fuel injectors on a VFR, in pounds of fuel
per hour, or lb/hr?



The only figure I can find is for fuel pump unrestricted flow which is 5
oz/10 sec, which equates to 14 gal/hr for just the fuel pump. At 72 degrees
F fuel is 6.25 lb/gal, or 87.5 lb/hr for the fuel pump WFO. Divided by 4
the max injector volume is 21.875 lb/hr that the in tank pump will support
before fuel starvation begins to occur in the rails. Of course (at least I
hope so) Honda engineering figured in some headroom for the fuel pump, so
would it be safe to assume that the stock Honda fuel injector flows around
19 lb/hr at max flow? That's only 13% headroom for the fuel pump, but 19
lb/hr is a standard number that I'm used to working with and is readily
available (i.e. no trick one-off injectors allowed).



Is the Honda stock injector type a high impedance or low impedance?



Also, does anyone know if a higher flowing fuel pump is available that can
be fitted, i.e. one from a Blackbird or Goldwing, if that becomes necessary.



Another data point...a modern manufacturer has deemed 19 lb/hr injectors
sufficient for a cylinder of 625cc at a 5500 RPM max, to generate 210hp from
the engine unit. The VFR is 195cc per cylinder, but 12000 RPM max, to
generate 100hp.



The reason why I am asking is because I can foresee fuel delivery system
modifications in the future, so I want to make sure I have the figures (and
equipment) noodled out beforehand. However, I also don't go running around
at WOT all the time, so if it's possible to fit a 24 lb/hr injector (if the
19 lb/hr figure is correct) and larger rails to combat very momentary
increased fuel consumption with the larger injector, I'll be fine with that.
The smallest injector possible is best as larger injectors tend to introduce
idle issues, and I'd like to have it run like stock but with greater
capability in the fuel system.



I have no BSFC figures.



Am I missing anything else?



Thanks -



Joe


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Joe, I have absolutely no answer for your injector query, but in a somewhat
related vein, Turbo City sells a modified fuel pressure regulator that
raises the pressure in the fuel rails from 36 PSI (stock) to 42 PSI.

I've got one on my bike with a modded airbox (de-flappered and
de-snorkelled) plus a custom dual underseat exhaust patterend after the WOLF
system, and it's been great. I really do need to dyno it and get some
emissions readings off it to see what my actual A/F ratio is like, but it
certainly "carburates" better with the mod FPR.

My ECU is stock BTW, no PowerCommander or the like.

http://www.turbocity.com/default.php...49366af7e0333c

and scroll down as required

HTH!


Later...ROB
'99 GL800RR-SP2
Spouse's- '90VTR250
Profile Page: http://profiles.yahoo.com/veefer800canuck
Website: http://www.geocities.com/veefer800canuck/index.html


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