- When it comes to building a competitive Time Attack car, a front wheel drive chassis
certainly provides significant challenges.
Having said that though, the DC2 Integra is probably one of the best front wheel
drive chassis out there and it's been competitive and effective in series
and classes all around the world.
We're here at World Time Attack Challenge with the Elusive Racing DC2 Integra,
and we're gonna find out exactly what's been done to make this car so
competitive in the club sprint class.
For a start we can see that the existing or factory B series engine has been swapped
out in favour of the K series engine.
While the B series is in it's own right, a very competitive engine,
there's no doubt that the K series engine is one of the finest to come out of the
Honda stables.
In this case a common swap has also been made using the larger capacity K24
bottom end, combined with the K20 series head.
A K24 on its own however is not enough to be competitive.
And we can see it's also been mashed with a large sized turbo.
In this case the EFR 9180, reaching straight for the top shelf of the BorgWarner EFR series.
Now that is quite a significant sized turbo to be fitted to what is still a relatively
small capacity, four cylinder engine.
And there's a lot that goes into making a large tubo like this provide a usable
power band.
In this case the engine is producing a full 20 psi by only 4500 RPM.
It is revved to 8500 RPM, so this actually provides a really wide and usable power
band to the driver.
In order to make this engine reliable under the strains of the sort of power
being produced and Time Attack duties, it's been fitted with the usual
range of upgraded internal components, in this case fitted with a set of Manly
connecting rods, and a set of forged aftermarket pistons.
In this case the compression ratio has been set to 9:1 which is suited to
the use of the E85 fuel.
The key to achieving that power band however really comes down to the
cylinder head.
In this case it has been ported in house by Elusive Racing.
It's also fitted with a full suite of Supertech valve train components.
This includes the Supertech aftermarket valves, along with a double valve spring kit.
The cams fitted though are the real secret sauce here, and unfortunately
we weren't able to pry out too many details around what cams have been
fitted, sufficed to say that a lot of testing and development has gone
into the exact profile chosen.
I can however confirm that the VTEC mechanism has been retained,
along with the continuously variable cam control on the inlet cam.
And that continuously variable cam control is really important in broadening
out that torque curve and helping to get that turbo up onto boost.
In terms of the power output, at the moment the car, as it sits here, is producing
420 kilowatts at the wheels on that 20 psi boost mark.
Now we may be asking ourselves then, if 420 kilowatts is the power aim,
why go with such a large turbo that's capable of producing somewhere
in the region of 700 plus kilowatts flywheel.
And the key here is that that turbo was purposefully chosen in order
to deliver the power in a way that's most usable by the driver.
And this is really the key to a front wheel drive chassis.
A small turbo that can tend to come on boost very quickly at low RPM,
can overwhelm a front wheel drive chassis and cause wheel spin.
So this turbo has been selected in order to try and optimise that power delivery
and try and get that power to the ground without running into traction issues.
Lastly while we're talking about that turbocharger, you can see that the
exhaust housing is a split pulse design.
And the exhaust manifold has been designed in order to make the most
of that split pulse housing.
This again is one little aim in trying to bring that turbo on boost just a little
bit earlier.
That split pulse exhaust housing or exhaust manifold design also entails
the use of twin external wastegates for boost control,
one external wastegate is plumbed up to each side of the split pulse
exhaust manifold.
Moving across to the intake side of the engine, it's fitted with a Skunk Ultra
inlet manifold and the design of this manifold is quite unique in that you
can see the drive by wire throttle body is actually fitted to the underside
of the inlet manifold and the design is trying to optimise the air flow into
each cylinder.
And this can often be compromised with a conventional plenum design
where the throttle body is fitted to one end of the plenum, this can help focus
or improve the air flow to some of the cylinders and sacrifice air flow to the
others, providing a flow distribution problem.
Now that Ultra inlet manifold is also fitted with two sets of injectors.
So that's eight injectors that are controlled in a staged manner.
This is consisting of eight Bosch 1650cc injectors and the idea with
that staged injection is that it allows the engine to start and idle on only
one set of injectors where the fuel requirements are less,
and then once the driver gets up in the rev range, and is using more boost,
and requires more fuel flow, the second set of injectors can be
brought into use providing the flow of fuel,
that's required to keep the engine happy.
We'll move on now and talk about the electronics package.
And this consists of an Emtron KV8 ECU which is really the mainstay
of the whole car.
This controls the engine, as well as also controlling a gear change
ignition cut through the PPG four speed H pattern gearbox.
Now that H pattern gearbox uses a strain gauge that is fitted to the
gear lever, this means that the driver doesn't need to use the clutch
during the upshift and doesn't need to back off the throttle.
This means that turbo stays on boost, and obviously improves the acceleration
of the car when at full throttle.
As we'll already alluded to with a front wheel drive chassis,
we're very much limited to how much power can be put through the front
wheels and here again the KV8 ECU is being used to optimise things.
First of all the boost control is adjustable relative to what gear the car is in,
and the boost can be stepped up through the gears.
Another key aspect here though is the boost targets are also configured
relative to throttle position.
And this allows the boost to be reduced as the driver backs out of the throttle.
And in a conventional turocharged car, what we can find is that the boost
and also the torque output of the engine is very non linear.
What I mean by this is if the driver backs off to 50% throttle,
it's likely that the engine may be still putting out anywhere as much as
80% to 90% of the torque that's available at full throttle,
and this makes it very hard for the driver to balance the car mid corner,
and control traction.
So y adjusting that boost and reducing it as the driver backs off the throttle,
it allows a lot more control of the car.
Backing up the KV8 is also a Motec PDM or power distribution module,
and this takes the place of conventional fuses and relays, and this essentially is
a steady state way of controlling the power distribution to all of the functions
in the car.
This is much more reliable than conventional fuses and relays,
and it's also much more configurable.
The other aspect of the electronics package here is the Motec C125
dash logger.
This doubles as a drier display, giving the driver all of the information he needs
while out on the track, and it also is a logging centre, so all of the information
from the chassis, as well as the Emtron KV8 is logged into the Motec C125
for analysis later back in the pits.
Now a key aspect with that C125 dash logger as well, what's really important
to understand is that when the driver's out in the heat of battle,
you don't have a lot of time to pay too much attention to what is being
displayed on the dash.
Now under normal conditions when everything is working right,
the driver is only relying on the shift light module as part of that driver
display, letting him know when to pull the next gear.
However the tricky part here is that if something goes wrong,
let's say for example the oil pressure or fuel pressure falls out of the bounds
that the tuner is happy with, then the Motec C125 can also trigger
a driver warning.
Now this will then bring the driver's attention to the fact something isn't right,
and he can glance down at the dash and read the message,
letting him know exactly what is wrong.
Now it's important to mention here that this car was only completed
a few days before its debut here at World Time Attack Challenge,
and that's why it is currently running at a relatively low power and boost setting.
We're sure that once it's been refined and tested a little bit more thoroughly,
it's going to be a really serious contender here in the Club Sprint Class.
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