Dual fuel PFI rails....

[Charles Brooks]

Why not "T" into the supply line before the fuel rail and use the existing fuel rail? You could use two solenoid valves, one on the supply line and one on the return line so that you don't mix the two fuels you're trying to run. It would take a bit longer for the alternate fuel to get to all the injectors but it would be MUCH simpler to plumb.

Charles Brooks

---------- Original Message ----------------------------------
From: Barry Tisdale <btisdale at cybersol.com>
Reply-To: diy_efi at efi332.eng.ohio-state.edu
Date: Mon, 14 Jun 1999 21:02:05 -0400

>Something got lost in translation here, I think.  (BTW, was using my wife's account for the original message - I'm back home again).

DUAL fuel; I'd need *two* parallel holes drilled the length of the bar.  Cross-drilling the two longitidinal holes where the injectors will be placed, plugging the access opening to the outside of the rail.  This results in two parallel holes, connected by cross-holes where the injectors will go.  Drill the injector feeds into this hole, between the long parallel holes, so's one injector can be fed by either of the two 'logs'.  One log would carry pump gas, the other, the fuel of your choice, probably avgas.  Two separate circuits, tanks, pumps, regualtors, etc. It would take about 0.2 sec for the fuel transition to occur; the volume of 'old' fuel to be flushed out of the common volume before the injector saw 'new' fuel.

Only problem is the drilling of two parallel holes in, say, a 1" x 3/4" bar, about 9" long - say, 5/16" holes & cross-drillings.  Is this do-able??

Assembling out of tubing & welding all the fittings would be tedious, at best, and surely beyond my skills.  If I had the 9" bars drilled, I could probably take it from there.

Technically, any comments?  Surely, this isn't the first time anyone has thought of this; anybody done something similar?  Probably ideal is a manifold w/ 2 injectors per intake port, but this is *really* beyond my capabilities.

Sincere thanks for any feedback - Barry