Hello Paul,

  Here are four pictures of P-port and the in-housing injection holders.
 This housing is one of several scrap housings I am machining to get the
 entrance angle and component dimensions finalized. These four pictures
 are from last August's work and don't show the finished bores yet.
 The P-port will have an outer step bore similar to the injector holders.
 I am extremely happy with the hardness and toughness of the DEVCON Al
 product.  Only one trouble is the consistency is a little softer than
 taffy so as you can see, it is easy to end up with inclusions.  If you
 work fast and use a technique like applying frosting on a cake, then
 good results can be obtained.  Any hole can be drilled out and filled.
 The company sells another slightly softer epoxy that pours.  I assume it
 has more solvent in it.

 I was very happy with how the injector area worked out and was able to
 get the correct and final dimensions with this one housing.  As for the
 P-port area I had to add about 6mm more along the bottom for the slide
 throttle to be supported correctly.  For this test work, adding epoxy is
 not a problem as it sticks to a preexisting epoxy when roughened up a
 bit.  As you can see it sticks well to prepared alumunim and is damm
 near as hard.  It machines VERY nice.

 Can it done with your straight-in approach?   Yes why not?  Bend up some
 thin aluminum sheet into the proper wedge profile.  Alodize it. Fix this
 fence in place with hot glue gun on the outside.  Epoxy should be made
 extra high and milled down to final dimensions. To save expensive epoxy
 add a 40mm wooden or plastic dowel in the area where the inlet will be
 bored.   DO NOT PREHEAT to make it easier to pour.  Follow the
 directions for best results.

 Doug in Japan

 That 12.5 degree tilt looks like a real mechanical advantage.
 I hope you can find a dyno over there to get some good numbers
 on the pros and cons of your version. BSFC and HP.


 Paul Lamar

Paul, With this approach why not bolt two housings together with a
center section between and the dowel pins then machine
that assembly P-port section flat so that a slide throttle can be hard
mounted directly to the housings?

Fred O.

I think I see what you are driving at. That might work.
I'll have to do a 3D and see if that is feasible.

Paul Lamar

Paul,

I bought the taffy consistency product.  As Lynn mentioned years ago, and
repeated yesterday in almost the same words, the product held up in the
exhaust port area in his kart motor.

Present rotor housing as shown will use two (2) high flow injectors each
should will flow enough fuel, for my HP needs.

Fred mentioned correctly that to use a horizontal  slide throttle you
have to machine the intermediate section.  Actually you will have to
shave the front housing as well and then you will probably interfer
with other items you want to mount there.  Personally  I think the
present slide throttle is just too long and I would suggest using two
smaller units.   Larry's design might work there however as it has the
control mechanism coming from the middle.

Doug in Japan