UltraVair single Carb & Motor mount

[Steve]

This is the Mike Pastor LE... Both carb setup and motor motor configuration are out of the norm but they have performed well...The carb is a Mikuni VM-30...

The engine turns a Tennessee Vw 54x22 prop 3300 rpm static... Under some conditions the long intake tube sweats and should be wrapped with hot oil lines from the rear mounted oil pump... Usually the tube wrap is with 1/4" ID refrigeration alum tube - the Ultravair needs 3/8 ID oil lines to keep the hydraulic lifters pumped up and the engine oiling properly... The solution decided upon was to use two oil manifolds with the 3/8" line entering or exiting the center of the manifold and two 1/4" oil lines from each end of the manifold going out to wrap the intake tube... The manifolds to be machined from
3/4"x3/4"x2.5" alum bar stock...

The motor mount is based from a plans accurate Vw sta 1 build... Use all .049 wall 4130 tube... 2 3/4" square tubes are bolted into the Vw mount holes across sta 1 - this is a hard mount - all the damping is done at the engine block attach points... The forward reaching round tubes are simply laid out in the shape sorta like the letter "M" forward to the engine block mount points... A round tube is run from the bottom of sta 1 up and forward to the top engine block mount on each side... All round tube is 1/2"... You need 8 rubber bushings for damping on the engine block attaches... (Do not use shock absorber bushings - the material is too hard and won't dampen properly - your engine will vibrate and shake at certain rpms)... Get bushings from McMaster Carr that are 40-50 hardness...

Photos attached:

Good Luck with your build...

[PropMan]

Steve, Thanks for posting this, I am considering the UltraVair for my XL. Already found a engine to start on, just have to pick it up!

[Steve]

Frank:
Interest Group:
 https://groups.yahoo.com/neo/groups/ultravair2/info

Buy new, stainless valves , guides, springs, lifters, forged pistons .040 over is good , a good oil pump from GPAS and bearings...
Recondition, cam, rods with good bolts,  jugs and all else re-purposed...

The oil sump as designed holds 5 cups filled right up to the lifter bosses - the 1/2 Vw cut-case hold 2 quarts but throws out a pint right away... The UV oil pickup tube needs to be turned deeper into the pan - make a sump there that holds another cup of oil as a 2fer...

Use anaerobic gasket sealer around the oil pump and oil galleries - GPAS has the product...

The engine rewards you with a another 75 rpm with a 2-1 exhaust - doesn't have to be pretty but you can fabricate with .035 wall from Grainger for lightness - put slip joints in it...

If you make the across top single carb intake system make the intake pipe go straight into the cross pipe (no sweep) that long intake has supersonic wave impulses flashing across it when an intake valve closes - you don't want that going out the carb...

Now if we could just find a cagey propman... Look for 3400 rpm static at 1400 degrees F EGT...

The conversion is a lot of work well rewarded with modest hard $ output and you have a good running /looking AV engine...
Steve

[PropMan]

Yeah,  and I can put a Chevy bow tie on it!