One of the standout cars from
Pike's Peak International Hill Climb
is the Enviate Hypercar built by Cody from LoveFab.
While we watched the car at the event,
we decided to track it down
and headed to LoveFab while the team
were working on the car between practice rounds
to get a more detailed idea of what makes this car tick.
The Enviate Hypercar you can think of as a beta prototype.
The team are intending to produce this car
in limited numbers to customers
if there proves to be demand.
Now the car was designed purposely to compete
in the unlimited class
at Pike's Peak International Hill Climb.
The unlimited class, as its name implies
is just that, there really are no rules
and this gives the team understandably
a huge amount of range to work within.
One of the areas that we're seeing
a lot of focus on in recent years is the
aerodynamic performance of the car.
Again, with no real rules to work from,
the team could really do whatever they wanted here.
So this is one of first places
that the team focused on.
Actually contracted Sebastian from Sauber F1 to develop
the entire aerodynamic package and body work for the car.
This all developed and then validated in CFD
before any of the parts were actually made.
The CFD at this stage suggests that the body work
should develop somewhere
in the region of about 650 kilograms down force
at a 150 kilometers an hour
and at a theoretical speed of 300 kilometers an hour.
This extends to in excess of 2,000 kilograms.
So you can see the importance, the value
of that down force.
There are some challenges with designing an aerodynamic
package like this.
One of those big challenges is,
not so much in achieving the down force,
again with no rules
that's actually a relatively simple part,
but the biggest challenge is getting that down force
and maintaining an aerodynamic balance.
What I mean by that is a balance of down force
from the front and the rear of the car.
If that balance doesn't remain stable,
it can have a negative impact on the handling
and performance of the car.
One of the challenges with cars running high levels
of aerodynamic down force is that it actually
has some negative impacts on the suspension design.
And what I mean by this is if we took a
conventional suspension design
and then we added a huge amount of aerodynamic down force
at high speed the car can actually end up
running on the bump stops.
One of the options to counter this
is to run exceptionally high spring rates.
Of course that has its own negative side effects.
The team have chose to use what's known as a third spring
or a heave spring arrangement
which involves a third shock absorber and spring
at both the front and the rear of the car.
Now this shock absorber does nothing
when the individual wheels are absorbing bumps
or running over bumps
or alternatively when the car is rolling in a corner.
However when the car starts to compress
under hard acceleration, hard braking,
or of course the aerodynamic down force,
that's when the third spring comes into action.
This allow us relatively normal spring rates
to be run on the main shock absorbers
and of course this allows a good level
of grip as the car goes through corners and over bumpy
undulations in the track.
Moving on to the rest of the car
we'll focus, first of all, on the engine package.
This is actually a relatively low-cost engine.
It's an LS based V8.
It's a 5.3 liter V8 and it's relatively common
in a lot of GM trucks.
These could picked in the wrecking yards in the US
for as little as four or five hundred dollars.
So it's a really cheap place to start.
Now, of course, with twin turbos added into the mix
that stock engine was never going to hold up
for very long.
In order to make sure that it was going to be reliable,
the team have stripped that bare engine,
they've fitted a K1 crankshaft and K1 connecting rods
and instead of 9:1 JE pistons,
the 9:1 compression is obviously more suitable
to the boost pressure that is now being run.
Of course there's also a
modified camshaft grind fitted to the engine
and ARP head studs are fitted to help clamp
the cylinder heads to the block a little bit better.
Moving on to the turbo package,
the engine is fitted with a pair of Garrett GTX 3576
turbochargers with 0.82 exhaust housings.
At the moment, the team don't have any solid power numbers
as the dyno of the engine was initially setup on
would only hold up to about 7 PSI and about five and a half
thousand RPM.
Where the engine was producing 550 wheel horse power.
At Pike's Peak in practice so far,
the team have been chasing a few issues
which included a boost leak
which was limiting boost to only 16 PSI.
Ideally the team want to be running
somewhere in the region of about 20 PSI
where they're anticipating the engine will be
making an excess of a thousand horse power.
With the high level of down force
that this car can produce this obviously
improves the car's ability to corner
and in particular the amount of lateral g-force
that the car can develop in the corner
is immense in comparison to a run-of-the-mill road car.
This creates another problem
with the engine's lubrication system.
And if the engine was fitted with a conventional
wet sump lubrication system,
the oil can literally be forced away from the oil pickup
and result in oil starvation
and damage to the engine bearings and crankshaft.
To combat this, the team have gone down
the common path of fitting a dry sump lubrication system.
This includes an external oil pump
that's driven from the crankshaft
which scavenges the waste oil out of the engine
back to a remote oil reservoir.
From here, the oil is then pumped back into the engine
and this ensures that even under exceptionally high
lateral g-forces, or for that matter,
acceleration and braking
the engine is always going to have
a constant supply of oil pressure.
With the engine being mid mounted,
this does pose a few limitations
on what gear boxes can be used.
Cody has gone down the common path for mid engine
vehicles of using the Porsche G50 transmission.
Now at the moment,
this is still a conventional synchromesh gearbox
which means that the driver needs to use the clutch
on both the up shifts and down shifts.
Particularly in the unlimited class at Pike's Peak,
this would be one of the few cars
that isn't running a sequential dog box.
In fact, most of the cars competing
are using paddle shift which makes it much easier
for the driver and allows the driver to concentrate
solely on driving the car
and particularly on the downshifts
achieving maximum braking force.
Now when it comes to the braking package
fitted to this vehicle,
this is also relatively unique
and it's fitted with a set of RPS carbon-carbon
brake rotors and a set of StopTech calipers front and rear.
Carbon-carbon offers some really
big improvements or advantages over a conventional
steel rotor.
Particularly the weight of the rotor is much lower.
This reduces the unsprung weight
but another aspect of this is it also reduces
the rotational weight.
You could think of this just the same as if you fitted
a lighter flywheel to your engine.
It's something that needs to be rotated
when the car is both accelerating and braking
and by reducing the moment of inertia on the brake rotors,
this can allow the car to both accelerate
and brake quicker.
The other aspect of the carbon-carbon brake package
is that it does work at very high temperatures.
But conventionally this actually has its
own set of drawbacks
because most of the carbon-carbon brake packages
on the market, will work at exceptionally high temperatures
making them ideal for perhaps for circuit applications
but they typically don't work very well
at low temperatures and may only start working properly
once they get in excess of perhaps three or four hundred
degree centigrade.
The RPS carbon-carbon package is designed
specifically for this purpose of hill climb racing
where there isn't an opportunity
to get a lot of heat into the brakes.
The carbon compound used in the rotors and the brake pads
allows really good brake performance
from as low as about 200 degree centigrade
through to around about 700 degree centigrade.
So it's a very wide range and it's going to make sure
that the brakes are effective right from the start line
right to the very finish of the hill climb.
Moving on to the electronics's package.
The engine is managed via a Haltech Elite 2500 ECU
and there's a few additional sensors
that have been fitted to the ECU.
Specifically due to the Pike's Peak Hill Climb setup.
In particular, the turbochargers are fitted
with turbo speed sensors
and this allows the team to see exactly
how hard the turbochargers are being worked
and where exactly they are operating
in the compressor map.
At the same time,
exhaust manifold back pressure senors
or E-MAP sensors are fitted and again
this is just another input so that the team
can make sure that they're getting the most performance
out of the turbochargers and the engine
and the very thin atmospheric conditions
that we see at the summit of Pike's Peak
at about 14,000 feet.
In the cabin there is a Haltech dash logger
and this is really a display for the driver
as well so that the driver knows exactly
what's going on.
There are warning alarms on the dash
that will alert the driver to any problems.
For example, the oil pressure is too low
or the engine coolant temperature gets too high.
More importantly, when everything's going well,
the dash also functions as a shift light
to let the driver know when it's time to change gear.
Making sure that he is using all of the
available rev range and optimizing the performance
of the engine.
The car's already proven to be a fierce competitor
setting second fastest time today here
in the practice in the middle section of Pike's Peak.
And we really look forward to seeing how it goes
in competition on Sunday.
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