Street-Legal Jet Powered VW Beetle
This is a my street-legal jet
car on full afterburner.? The car has two engines:
the production gasoline engine
in the front driving the front wheels and the jet
engine in the back.? The idea is
that you drive around legally on the gasoline engine
and when you want to have some
fun, you spin up the jet and get on the burner
(you can start the jet while
driving along on the gasoline engine).? The car was built
because I wanted the wildest
street-legal ride possible.? With this project, I was
able to use some stuff I learned
while getting my fancy engineering degree
(I have a PhD in Mechanical
Engineering from Stanford University) to design the car
without the distraction of how
other people have done it in the past - because no
one has.? I don't know how fast
the car will go and probably never will.?
The car was built to thrill me,
not kill me.? That doesn't stop me from the occasional blast
The car is
licensed here in
California, new cars have
smog inspections so if you modify the engine, it is likely
to fail the
inspection and you won't be able to drive it on the street.?
some exempt engine modifications (ex. after-cat mufflers - big deal)
that will allow you to add 1350 hp to a new car.
Car was built
to look as if VW delivered the car this way.? It handles
fine and is
safe.? I was thinking of putting it into an import car show
promoter told me that it looked too plain and recommended
put some decals on it, lower it, and put on some aftermarket
Sure kid, put on some flimsy wheels won't take a curb and
don't center on
the hubs, lower the car so the tires rub and get cut by
using springs that bounce me all over the road, and advertise
that couldn't engineer themselves out of a paper bag.?
I would have
thought the 14" diameter tailpipe was enough for him but
it wasn't.? Response from the hot rod magazines has been slow.?
editor told me that is because I didn't use anything they advertise.?
response to driving it on the street and going to the hot rod shows
Custom Car Show, Grand National Show in
and the Detroit
Autorama) has been fantastic.? This car attracts crowds
than any '32 Ford, '69 Camaro, or decaled Honda.?
The Beetle was
chosen because it looks cool with the jet and it
off well.? Remember the
Hurst wheelstanding Barracuda
Glass"?? Well, this is "Jet Under Glass".? Air for the
enters the car through the two side windows and the sunroof.?
It's a little
windy inside but not unbearable.
hatch release switch on the driver's door activates
latches (one on each side) and the hatch pops open just
production car.? The "hatch not closed" warning light works too.
Here you can
see the split in the tailpipe after a
rude burner pop.? All fixed and
now.? The heat blanket keeps the
from melting when the jet is operating.?
The back of the
gauge panel was kept open to give the car a techie look.?
to talk about.? The car's an engineering device, let's see
engineering thingies.? The aluminum panel was designed in
cut out of billet, bead blasted, clear annodized, and
then the labels
for the switches were milled into the front using a font
matching the VW
cluster.? Little details like the holes having flat sides
switches don't spin and exactly matching the contour of the
added time to the project.? Several versions were made out of
first to get the layout and lighting right.? From the back,
reminds me of the 1970s McLaren CanAm cars.
The first thing
I did when I got the car was to cut the hole in
for the engine.? Made a fancy jig out of a tripod, a
a lawnmower wheel to mark out the cut and went
at it with a
pneumatic saw.? Then finished it off with
files.? No paint required.? Didn't even chip.?
The hole was
tricky because it goes through 3 layers
(bumper and two
layers of metal) and it's a circle projected
surfaces.?? Just finding the centerline of the car
trivial.? Worrying what my neighbors would say if I
the back of a brand-new car made me REAL careful.?
I believe the
hole is within 2 mm.
There are three
gauges for the jet: %RPM,
and Turbine Inlet Temperature.?
important is turbine inlet temperature.?
If you exceed
about 650 degrees C for very long,
you damage the
engine.? This is critical on start-up.?
want a "hot-start".? The throttle for the
jet engine is
located next to the gear selector.?
It is a
lever and has three buttons: Cool, Big-Fire,
Afterburner.? "Cool" leans out the engine and
to lower the turbine inlet temperature if you
hot-start.? To light big-fire or the afterburner,
you hold a
button down and 1/2 second later, press
button on the floor.? Then things happen!?
the kerosene level gauge in front of the gear selector
(jet fuel is
mostly kerosene) and the bud vase missing a rose.?
back here.? The force from the jet is tied to the vehicle
sandwich plates inside the car bolted to contoured aluminum
that were slid into the frame rails.? You can see the billet on the
with a hole in its center, welded to the plate with 4 bolts.?
Used helium as
the inert gas and a lot of current to weld that chunk
To return the car to its production height, adjustable
perches were used.? Same spring rate, just corrected the ride
Drives and handles fine.? Kerosene is stored in a custom 14
baffled, foam-filled kevlar fuel cell in the spare tire well.? Two
fuel exits in
the back: a -12 on the left side and a -10 on the right.?
goes to a shutoff, then a Barry Grant pump (one of the few
parts on the car), then up into the car where it sees a filter,
regulator, and an electrical shutoff valve before feeding the engine.?
goes into a shutoff, then a 1.5 hp, 11,000 rpm, 24V custom
pump.?? Pump is magnesium and can maintain 100 psi at 550 gph.?
From the pump
it goes into the car to a filter, then a large regulator,
and then to the
afterburner solenoid and the big-fire solenoid (to left
and feeding bottom of tailpipe through orange covered hose).?
Fuel system was
tested for flow capability.? Above the big pump you
can see the
relocated gasoline cap actuator and all that black stuff on
the right side
is the stock fuel evaporative control equipment.? All
feeding solenoids and pumps have fuses, relays, kick-back
minimize contact arcing, sealed connectors, and use
wires of a gauge giving a maximum of 1V drop over the circuit loop.??
The engine is a
General Electric Model T58-8F.? This is a helicopter
engine that was converted to a jet by some internal
and a custom tailpipe.? The engine spins up to
RPM (idle is 13,000 RPM), draws air at 11,000 CFM,
rated at 1350 hp.? It weighs only 300 lbm.? It grows
as it warms up
so the engine mounts have to account for this.?
The mounts in
the front are rubber and the back are sliding
rubber.? The structure holding the engine was designed
element analysis and is redundant.? Strong, damage
light.? Second battery and fuse/relay panel on the
halon fire system and 5 gallon dry sump tank on left.?
motor is in the nose of the engine.? 700 A of current
goes into that
motor for 20 seconds during start-up.? Due to
must limit starts to three in one hour.? Big screen is to
(foreign object damage).? Jet keeps sucking the
rose out of the
bud vase on the dash!
A lot of
attention to details in the car.? Note the aluminum block
the halon gas line, pull line, harness to engine,
pressure line.? Rectangular tank under inlet screen is for
drains.? Note temperature gauge and shutoff valve
sump tank.? 3 gallons of turbine oil at $25/quart (ouch!).?
paint matching exterior of car was used inside the car.?
It is not
easy to paint around a lot of bars, etc while crouched in a car,
dusty home garage, avoiding drips, and with your wife
the fumes will cause brain damage in the kids.?
with two-stage where you have multiple coats and
times.? Kids passed their grades so I guess
was minimal, but more importantly, the paint turned out great!
action.? The other guy wimped out after a few "big-fire"
demonstrations.? What you see in the picture is about one-twentieth
the full size
of the fireball.? Guy standing beside car had never seen
it run before
and was smiling ear-to-ear throughout the show.?
launched, I would have burned him to a crisp.? Well, live
We get this a
lot.? A police officer picking at his nose while trying
to figure out
what to charge me with.? Notice the hopeful anticipation
of us on
the right.? We're rooting for him and offer suggestions
unfortunately, the California Department of Motor Vehicles
anticipate such a vehicle so he's out of luck.? Hmmm,
the car has two
engines making the car a hybrid so maybe we
in the commuter lanes along with the Toyota Priuses.
The car was
built in this garage.? Paint, welding, everything except
work.? That's me standing beside the engine that is out
car for some fuel controller work.? The orange line is for the
There's one on the other side too.? Here you can
make out the
four rows of variable inlets/stators at the front of
engine.? Their angle changes with engine speed and is used
compressor stall.? There are 11 compressor stages and
stages.? The engine's pressure ratio is 8.3:1.? That's how
you work on a
jet engine.? Stick it on its end.? Easy to store them that way too.
wife's Honda Metropolitan scooter.? She wants it to go
than 40 mph.? So I have these two little JFS 100 jet engines
and I am
thinking how to put them on the scooter.? Engines are
50 lbm each so
weight is an issue.? Will probably use air-start with
fiber tank of compressed air.? That saves weight since
then not be needed.
Looks cool from
the top.? Will want to make
housings to go over the engines just
like on a DC-9.
the back too.? Should get the scooter going.?
On one jet
engine alone, this engine will get a kart up to 60 mph.?
Looks like I
have a lot of spare wire left over from the Beetle job
to do the
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