Dual fuel PFI rails....

[Frederic Breitwieser]

Based on your stated skillset, you might consider two seperate rails, unless you come up with something a little more clever.

How about an aluminum block a few inches long, at 3/4x3/4, that's something you can put in your drill press and bore straight down.  being rectangle you can use your press's vice to hold it still.  Then, after your two holes are bored in for the two injectors, you can tap the end, attach a fitting, then daisy chain the rails that way.  I anticipate your dual injectors run in series on the intake runner, meaning single file along the runner rail.

Corrent?

Barry Tisdale wrote:

> 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