‘Powerage’

1949 FL Harley Shovelhead
– Big bore kit 1380cc
– T28 hybrid turbo from a Nissan skyline
– Custom 3 inch exhaust stainless dump pipe
– Custom stainless exhaust manifolds
– Custom Mazda RX7 Intercooler and hand made air duct altered to fit under the fuel tank
– Custom stainless inlet plenum
– Heavily Modified Harley super e carburettor (boost referenced , modified to accept holley jets
and secondary accelerator pump)
– Holley remote fuel bowl (This is a fuel bowl from a V8 car which has modified to fit the Harley
carburettor)
– Malpassi rising rate fuel pressure regulator
– Electric fuel pump
– blow off valve
– Adjustable boost controller
– K&N air filter
– Electric engine oil scavenge pump
– Remote engine oil filter
– Custom made stainless oil tank which has been relocated to the frame down tube
– Braided oil/fuel lines
– Custom battery tray also relocated to the frame down tube
– 2 stage rev limiter mounted to bar riser
– Dynatek programmable ignition
– 5 speed gear box
– Billet aluminium open primary
– Forward controls
– Custom fuel cap
– Autometer boost and air/fuel ratio gauges
– Exile cycles rear sprocket brake
– 40 spoke wheels
– Custom seat pan/rear fender. A stainless steel heat shield is also located between the seat
and turbo.
– Drag bars
– The frame has been raked 5 degrees.

This is how it all works-
Runs a remote holley fuel bowl from a V8 car due to the original carburettor not being able to handle more than 2 psi fuel pressure (Flooding). The original floats were not buoyant enough to handle the fuel pressure so they were discarded and the holley fuel bowl/float took its place.
Currently running 6 psi fuel pressure. To get the carb to run correctly, the remote holley bowl and the original carb bowl housing had to be boost referenced to maintain a correct float level under boost.
A secondary accelerator pump was added due to a hesitation when cracking the throttle with the big inlet plenum. The accelerator pump from the holley bowl was utilised with a custom linkage and custom made nozzle fitted before the carburettor venturi.
The Malpassi rising rate fuel pressure regulator maintains 1 to 2 psi more fuel pressure than boost pressure (eg) 15psi boost-17psi fuel pressure. This is done as the fuel needs to be under pressure to get through the jets when the carburettor is under boost.
The super e carburettor emulsion tube was also modified to accept holley jets. this was done due to the factory super e jet kit being maxed out while tuning. The holley jet kits have many larger size jets available and i found it much easier to tune swapping jets rather than drilling the original ones.
So far this bike has been wound up to 22 psi on pump fuel with no problems, and currently running a conservative 15 psi on the street.
A electric engine oil scavenge pump was added due to the shovel head engine producing some back pressure in the crankcase (factory feature). The turbo oil drain was originally fitted to the crankcase but wasn’t very happy with the back pressure, so the electric scavenge pump now returns the turbo oil directly to the top of the custom oil tank.
It has taken 5 years to build (and iron out the bugs) but we are pretty happy with the result
Cheers.

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