-
- With a 450 horsepower naturally aspirated
four litre V8 that revs all the way out to
-
8700 RPM, our Toyota GT86 racecar is
a pretty competitive and fun car to drive
-
out on the racetrack.
-
While we've owned this car now for around about
12 months, we haven't actually haven't talked
-
too much on camera about what makes this
car tick.
-
So that's going to be the basis of this video.
-
Let's start with that engine and this is based
around the Toyota 1UZ-FE four litre V8.
-
This is a hugely popular engine, particularly in
New Zealand and Australia for engine swaps,
-
and you'll find these engines fitted to all
manner of different chassis.
-
Now in stock form, these engines actually
aren't that inspiring, with the four litre
-
capacity, they only produce somewhere in the
region of about 300 horsepower.
-
However, with the variable valve timing
mechanism on the later VVT-i based engine,
-
they do produce quite a nice wide powerband.
-
Now when we got involved with this car,
it was actually owned by one of our
-
customers.
-
He had started with the car brand new straight
off the showroom floor back in 2012
-
and he'd gone through a variety of different
engine combinations, starting with the
-
stock FA20, adding a supercharger kit,
then swapping to a turbo kit before deciding
-
that there really is no replacement for
displacement.
-
After talking through his options with us,
he decided to fit a stock standard 1UZ-FE.
-
He also backed this up with a Toyota R154
five speed gearbox which is more than
-
capable of handling the torque and power
from the 1UZ-FE.
-
We only stepped in to supply the electronics
and tuning which is a MoTeC package
-
we'll talk about shortly.
-
Understandably with that stock engine,
the power wasn't overly inspiring and after
-
only a few months running the car,
the old owner decided that he needed more.
-
Here in New Zealand, the Toyota 1UZ-FE
engine is a popular base for stock car
-
engine builds.
-
And in fact there is a class where these are
used as a control engine.
-
They must maintain four litre capacity and
they're limited to a 10:1 compression ratio.
-
So the owner of the car purchased a ready
built race motor, this included a set of stock
-
pistons with that 10:1 compression,
a set of stronger H beam connecting rods
-
and really where the power all comes from
is the modifications to the cylinder heads.
-
The cylinder heads are ported using a CNC
porting program and they're fitted with a
-
much more aggressive set of cams and a
matching set of valve springs.
-
This is also mated to a modified Holley
intake manifold that's more likely to be
-
found on a GM LS V8.
-
The 10:1 compression ratio means that the
engine is quite capable of running on normal
-
pump fuel with nothing too exotic and no
ethanol blends required to keep it happy.
-
Given the increased airflow in and out of
the cylinder heads thanks to the cams and
-
the porting, the engine now revs as I
mentioned, all the way through to 8700 RPM
-
and it actually produces peak power right on
that maximum RPM rev limit of 8700.
-
Speaking to the company that was responsible
for designing and building this engine,
-
we did investigate revving the engine a little
bit further but given that this particular
-
cylinder head is only fitted with a single
valve spring, we were advised to maintain
-
a maximum limit of 8700 so we did what
we were told.
-
Getting good reliability out of any engine
that's used on a racetrack often requires
-
modifications to the oiling system.
-
This is because of the extreme lateral and
longitudinal g forces that we're going to see
-
out on the racetrack.
-
In this case, the stock wet sump system was
replaced with a relatively basic dry sump
-
system.
-
It uses an external three stage dry sump pump
that's mounted on the driver's side of the
-
engine block.
-
This includes two scavenge stages which
withdraws the oil and air out of the sump
-
and then pumps it to a reservoir that's mounted
in the cabin behind the passenger side of
-
the car.
-
There's another stage of that pump which is
the pressure stage, this draws the oil forward
-
from that reservoir in the cabin and then
pumps is through the engine.
-
This ensures that regardless what forces are
applied to the car out on the racetrack,
-
the engine is always going to have a steady
and consistent supply of high pressure oil
-
to all of the important engine components.
-
While the original 1UZ-FE VVT-i engine that
was fitted to the car did retain the variable
-
cam control, with the much more aggressive
cams that use now a lot more lift and
-
overlap than stock, there wasn't the capacity
or ability to retain that variable valve
-
timing system.
-
This is because there simply isn't the
ability to swing the cams or move the
-
cams significantly before we'd run into
problems with piston to valve contact.
-
Now that's not necessarily such a problem in
our application anyway because now we've
-
swapped to a six speed sequential
gearbox with much tighter ratios
-
and this means that the engine out on the
racetrack is normally operating over only
-
approximately a 2000 RPM rev range and when
we're only operating under such a short
-
rev range, there really isn't so much advantage
from being able to advance and retard the cams
-
while the engine is operating.
-
We'll come back and talk about that gearbox
shortly but before we do that I just want to
-
talk about the fuel system.
-
And this is something we actually battled with
with this car.
-
With a stock fuel tank, understandably they're
not designed to work well with high lateral
-
or cornering forces and in this particular
car we can easily see lateral g force
-
in corners of in excess of 1.2 or 1.3 G.
-
What that does, particularly with a factory
saddle tank where half of the tank is on
-
each side of the main north/south driveshaft,
it makes the fuel run away from the fuel
-
pickup.
-
It obviously doesn't take too long under
sustained high G cornering for all of
-
the fuel to run away from the pickup and then
the engine starves of fuel.
-
In order to combat that, what we've done
is we've fitted a Radium in tank surge
-
system on both sides of the tank.
-
This includes an in tank pump and a built
in surge system or anti surge baffle system
-
that holds the fuel around the pickup for
the pumps.
-
Now this isn't bullet proof though but
what we've done here is we've pumped the
-
fuel from both sides of the tank into a
common surge tank.
-
The surge tank is fitted with two in tank
pumps that then pump the fuel forward
-
to the fuel rails on the engine.
-
Now this engine is fitted with a fuel pressure
regulator in the engine bay, however it is
-
referenced to atmospheric pressure and it runs
at a fixed four bar.
-
So this is quite similar to what we'd see in
a late model car with a returnless fuel system
-
where the fuel pressure is constantly
maintained at four bar or 58 psi.
-
Now the fuel injectors actually used to
inject the fuel are a set of Injector Dynamics
-
ID1050x.
-
Now if you're thinking that these sound like
overkill, then granted they absolutely are
-
for a 450 horsepower V8.
-
There are a couple of reasons why we did
go with an injector that's a little larger than
-
we needed.
-
One of them was because we did want to run
on an E85 ethanol blend for sprint races
-
and this later on is going to allow us to add
a lot more compression to the new engine
-
that we've got planned.
-
The other aspect here is that using a large
injector means that our maximum injector
-
duty cycle is relatively low, even under wide
open throttle and high RPM.
-
And this can give us some benefit in
adjusting the injector timing to optimise
-
the way the fuel is delivered into the
cylinder, maximising the fuel and air
-
mixing and hence the amount of power that
we can extract from the air entering
-
the engine.
-
The electronics package controlling any late
model car is often challenging.
-
And in this case we're running a MoTeC M150
ECU.
-
Now the problem here is that if we just swapped
in any aftermarket ECU, while yes we would be
-
able to control the engine and make it run,
it's actually the integration with the
-
electronics in the rest of the car that can
be problematic.
-
In stock form the engine control unit as well
as the ABS system, also the traction control
-
and the dash cluster, all communicate
together over a CAN bus.
-
Now when we remove the factory engine
control unit and replace it with an aftermarket
-
standalone, that communication bus is no
longer there and we can find that this
-
causes problems with the operation of
the other aspects.
-
Another part of the factory car that we're
still retaining that relies on that
-
communication is also the electric power
steer.
-
So MoTeC have produced an ECU that
replicates the factory CAN bus messaging.
-
This means that all of the factory sub
systems still work as you'd expect,
-
but allows us complete control over the
engine tuning.
-
The particular ECU we are running is a
MoTeC M150 ECU however it's also
-
important to know that it is running the
Toyota GT86 engine swap package.
-
So this is why we can now remove the stock
FA20 engine, rewire the M150 to our 1UZ-FE,
-
we've got complete control over the
engine and also the rest of those electronic
-
systems in the car.
-
Using the M150 ECU also allows us to take
advantage of some of the advanced
-
motorsport or race functionality such
as traction control, which is very easy
-
to configure to suit the car, the track,
the conditions and the driver's preferences.
-
We've also got launch control in there,
a pit limiter which is essential for the
-
endurance racing we're doing, where there
is a 40 km/h pit limit that is strictly
-
enforced with penalties if you are caught
speeding.
-
We're also using of course the sequential
gearbox with clutchless shifting.
-
So incorporating the closed loop gear change
control and auto blip on the downshift
-
through the M1 really unlocks the potential
of that particular gearbox.
-
Speaking of the gearbox, while I mentioned that
originally the car was fitted with the
-
Toyota R154 gearbox, these are a big gearbox
that are plenty strong enough,
-
however they're pretty agricultural in their
shift quality which isn't ideal out on the
-
racetrack.
-
It feels a little bit like rowing a boat when
you're trying to change gear.
-
The other aspect with the R154 is that the
ratios weren't ideally suited to what is now
-
a relatively peaky naturally aspirated engine
that only makes peak power over a narrow
-
powerband.
-
The gearbox that we have chosen is the
TTI six speed sequential gearbox which is
-
locally made here in New Zealand.
-
We've seen these gearboxes be proven
time and time again in motorsport here
-
in New Zealand so we had the confidence that
they were going to be reliable with
-
our application.
-
The other consideration we made when
deciding on our gearbox was the ability
-
to have the gearbox serviced inside of
New Zealand and be able to source
-
components if we needed to repair the
gearbox really quickly and easily.
-
Fronting the gearbox, we'll find a Tilton
twin plate clutch mounted to a lightweight
-
chromoly flywheel.
-
The clutch is actually only used to get the
car off the start line or out of the pits.
-
Once the car is moving, the clutch isn't
necessary regardless whether we're
-
upshifting or downshifting and a key to this
is the Motorsport Systems strain gauge
-
gear lever.
-
The strain gauge gear lever sends a voltage to
the MoTeC ECU that tells the ECU whether the
-
driver is pulling back on the lever for an
upshift or pushing forward for a downshift.
-
Not only this, the strain gauge gear lever
tells the ECU exactly how hard the driver
-
is pulling or pushing on that lever.
-
So this way the MoTeC knows if the driver
is requesting an upshift or a downshift.
-
On the upshift, the driver can stay at full
throttle and as I've mentioned, no clutch
-
is required for the shift.
-
As the driver pulls back on the lever,
the MoTeC knows that the driver's requesting
-
an upshift and will perform an ignition cut,
a fuel cut or both to interrupt the engine
-
torque and allow the dogs inside the gearbox
to disengage and engage the next higher gear.
-
The downshift is a little bit different here
and obviously the driver will normally be
-
off the throttle and probably hard under brakes
when downshifting.
-
Here, the driver's going to push that lever
forward and the MoTeC ECU is going to
-
automatically blip the drive by wire throttle
in order to rev match for the next lowest gear.
-
So essentially this is very similar to how a
paddle shifted gearbox works.
-
Again with the paddle shifted gearbox the
clutch isn't necessary, only this time the
-
shift is a function of the driver actually
pushing and pulling on that gear lever.
-
Moving towards the back of the car,
we are still running the stock Toyota
-
differential however there are a couple of
modifications we've made here.
-
We've fitted a shorter 4.556 final drive and
instead of the factory Toyota Torsen LSD,
-
we're now running a Cusco 1.5 way clutch
plate LSD.
-
While the stock Torsen LSDs do work quite
well, in a race application what we can find
-
is when we're running over ripple strips
or curbs, we're inclined to end up popping
-
the inside rear tyre off the ground.
-
When that happens with a Torsen LSD,
all of the torque is fed to the wheel that's
-
now in the air and we instantly lose drive.
-
The clutch plate LSD ensures we're always
getting drive put to the tyre that's still
-
on the track.
-
We quickly found when we started running
this car that controlling the differential
-
temperature was a major problem.
-
In stock form there's understandably no
differential cooler so in order to address
-
this we ended up fitting a Cusco rear diff
cover and this allows an increase in the oil
-
capacity but more importantly, it provides some
AN fittings that makes it really easy for us to
-
integrate an external oil cooler.
-
This is controlled via the Ecumaster PMU or
power management unit and is automatically
-
turned on when the differential temperature
gets above 80°C.
-
With 450 horsepower and a bunch of torque
now being transmitted to the rear wheels,
-
the stock axles were the next weak link.
-
And while we have actually been battling
problems with axle reliability, right now we
-
are running a set of Driveshaft Shop 800
horsepower axles and so far they have proven
-
to be up to the task of one hour endurance
races.
-
While the stock GT86 does handle pretty well
on the road, it's obviously never designed
-
to be a racecar so there were some serious
considerations needed in terms of the
-
suspension package, the wheel and tyres
as well as the brake package in order to make
-
this car competitive and reliable on the
racetrack.
-
Starting with the suspension, we're currently
running a set of RaceFab suspension arms
-
in the rear, this is an adjustable lower control
arm that allows us to adjust our camber
-
and get that where it needs to be.
-
This is also coupled with a set of RaceFab
trailing arms and an MCA traction mod
-
mount which adjusts the anti squat
properties or geometry of the rear
-
suspension.
-
At the front of the car we've retained a
set of stock lower control arms,
-
although these are fitted with a set of
aftermarket Whiteline suspension bushes.
-
The coil overs that we are running in the
car are a set of MCA Reds from Australia.
-
MCA produce the suspension as a control
part for our local Toyota TR86 racing series
-
so they're no stranger to what valving and
what spring rates work well in the GT86
-
chassis.
-
To provide a little bit more adjustability
to the chassis and allow us to affect the
-
handling balance, we've also got a set
of Whiteline adjustable anti roll bars
-
front and rear.
-
To ensure the car will stop reliably on the
racetrack we are running a set of Endless
-
brakes on the front, specifically this is a
four pot caliper fitted with Endless'
-
endurance racing spec pad and a set of
Endless rotors.
-
We've also got a set of brake cooling ducts
feeding cooling air onto those rotors
-
which is essential, particularly for
endurance racing.
-
At the rear we are currently running a set
of D2 brakes off our other car however we've
-
got a set of Endless four pot calipers that
will be going on the rear over our off
-
season.
-
The wheel and tyre package starts with a
Wedssport wheel in a 17 x 8.5 inch fitment.
-
We've actually got three sets of these wheels
for the car and two of those sets of wheels
-
are fitted with a Michelin medium compound
slick.
-
The third set are retained for wet weather
use and are fitted with a set of Hankook
-
wet weather tyres.
-
When we took ownership of the car,
externally it did look relatively stock
-
and one of the things that we have done
over our season of racing is added some
-
very basic aero.
-
Now at the moment we've called this
backyard or ghetto aero and it was really
-
what we could get done in the two weeks
between two of our endurance racing rounds.
-
We do intend to address this over our off
season and produce something that is a
-
little bit more complete and hopefully
a little bit more effective.
-
However what we can see is that the car
is fitted with a plywood splitter that is
-
covered with a carbon kevlar weave.
-
We've also got a couple of canards fitted to
the front bumper or dive planes as they're
-
also known and this helps produce a little bit
more downforce at the front of the car.
-
You can see that there are a couple of
braces from the splitter up to a nudge
-
bar or bash bar that runs in behind the
factory front bumper.
-
It's really important with any of these
aero items to make sure that they can
-
actually support the loads that we're
expecting to see and with this particular
-
splitter, we can easily stand on the front of
it, bounce up and down and everything's
-
going to be nice and solid and nice and
reliable.
-
There's not a lot of point just addressing one
end of the car when it comes to aerodynamics
-
and on the rear of the car we have also
fitted a relatively basic rear wing.
-
And this currently is just mounted to the
boot lid.
-
In the off season we'll also be addressing
this with a proper chassis mount,
-
making sure all of the aerodynamic loads are
transferred down to the chassis rather than
-
just causing the boot lid to bend.
-
We'll also be fitting a better rear wing
element that's actually got some proven
-
data behind it.
-
While going fast is a lot of fun, we also
want to be able to go fast safely so we've
-
taken the safety elements of this car very
seriously.
-
When we took ownership of the car it was
fitted with a relatively basic six point cage.
-
Although there was nothing specifically wrong
with that design, one thing we did want to
-
add though was a set of side intrusion bars
on the driver's side.
-
This means that if we are involved in an
incident where someone drives into the
-
driver's door, we're hopefully going to be
protected by that side intrusion,
-
preventing injury.
-
The driver's seat is obviously another important
aspect of car safety, as well as making sure
-
that the driver has a really good feel for
what the car is doing.
-
Here we're running a Racetech head restraint
seat and this is one of their back
-
mounted seats.
-
So not only is the seat mounted at four
points on the bottom as with a conventional
-
seat, there is also a rear mount that attaches
to the roll cage.
-
And this makes sure that the seat is both
safer as well as more rigid.
-
We're also running a six point harness to
make sure that the driver is held securely
-
in the seat.
-
Out on the racetrack, there's a lot going on
in a short amount of time and it's very
-
difficult for the driver to monitor everything
while trying to get the most out of the car.
-
We've focused here on a few aspects.
-
First of all the car is fitted with a MoTeC C125
dash.
-
This is mounted in the stock gauge cluster
location and in normal circumstances really
-
the driver is only going to be focusing on the
shift lights, knowing when to pull the
-
next gear.
-
There is some other information that can be
displayed on that dash, particularly for
-
practice and qualifying we bring up our
current lap time as well as predicted
-
lap time and we can also present a lap
gain/loss function.
-
Basically showing whether we are doing
better or worse than a reference lap time.
-
The real value of that dash comes with
anything that goes wrong though.
-
It can monitor all of the inputs to the
dash as well as the engine control unit
-
and bring up a driver warning if anything
goes outside of defined parameters,
-
for example if the engine starts running
too hot, this can bring up a driver warning.
-
The driver can then look at the dash,
see what that warning is and decide
-
on the correct course of action.
-
The key with the MoTeC C125 is that it
is logging all of those parameters while
-
the car's out on the track for analysis at
a later point.
-
While the car is on the track we can also
monitor all of those aspects in real time
-
using the MoTeC T2 telemetry system.
-
So this uses a 3G modem to send all of that
data out from the car and it can then be
-
monitored by a laptop in the pits.
-
With a crew being able to monitor so much
information while the car's out on the track,
-
this offers a lot of potential for first of all
driver coaching during the practice and
-
qualifying sessions but also during the race
it allows pitstop strategy to be decided upon.
-
We can monitor in the pits the current fuel
burn so we know exactly how much fuel
-
is left in the tank and how much the car
is using for every lap.
-
This allows us to calculate the pit window
when we need to actually pit the car
-
in order to be able to get to the end of
the race.
-
We've also got the ability to monitor all of the
engine's vital signs and again warnings can
-
come up if anything goes outside the normal
operating conditions.
-
An interesting addition to our datalogging
package during the course of our racing
-
season was the Izze-Racing tyre temperature
and pressure monitoring system.
-
These are a sensor that goes inside each of
our wheels and allows first of all the air
-
temperature and pressure inside of the
tyre to be monitored.
-
This particular sensor also uses an infrared
temperature sensor that monitors the
-
carcass temperature on the inside of the
tyre.
-
All of that information is transmitted from
the sensor wirelessly to a receiver
-
and then that information is transmitted to
the MoTeC C125 dash via CAN.
-
Now in normal circumstances, understandably
the driver's not going to be monitoring this
-
while they're out on the racetrack.
-
However we've got warnings set up if one
of the tyres receives a puncture and the pressure
-
starts to go down, this information is also
transmitted via telemetry meaning that the
-
team can watch this information from the
comfort of the pits.
-
These days it's become quite common to
see a number of driver controls or
-
adjustments placed on the steering wheel of
GT3 style racecars and we've taken some
-
cues from this and made our own steering
wheel.
-
This allows the driver to control some of the
key aspects without needing to take their
-
attention off the steering wheel and driving
the car.
-
In particular on the steering wheel we've
got controls for the pit lane limiter.
-
We've also got controls in a multi position
rotary style knob for both traction control
-
and launch control.
-
We've also got the ability to control the
radio so that the driver can communicate
-
back to the crew in the pits.
-
On top of this there's also the ability to
change the information that is being
-
displayed on the dash as well as the page
layout on the dash and of course if there
-
is a warning message that comes up there
is a warning reset button.
-
If we happen to come up on some slow traffic
that doesn't want to get out of the way,
-
we've also got the ability to press a button
that will flash the headlights multiple times
-
automatically or if things get really nasty,
you can always hit the horn.
-
While the car has been a work in progress
over the time we've owned it and does
-
retain a lot of the factory wiring, we have
needed to add some additional wiring
-
into the car and we made the decision to
go with the Ecumaster PMU or power
-
management unit.
-
So this is essentially a solid state power
distribution module that electronically
-
controls the delivery of power to the
various circuits.
-
Now despite the fact that we are using
a MoTeC dash, a MoTeC ECU and an
-
Ecumaster power management unit,
all of these units speak together over
-
a common CAN bus.
-
Meaning that we can trigger outputs on the
PMU via CAN messages from the C125 dash.
-
Currently we're using that power management
unit to control the cooling pumps for the
-
gearbox as well as the differential, we're also
controlling both of the in tank pumps,
-
as well as the two high pressure pumps
inside of the surge tank.
-
One of the key aspects with the PMU is
that the communication bus goes both ways.
-
So it will also send information on current
draw as well as load on each of the channels
-
of its outputs back to the MoTeC C125 dash
for logging as well as being able to send
-
that through vis telemetry back to the pits.
-
This allows us to monitor all of those channels
and can give us some insight into something
-
that may be starting to fail such as a fuel
pump that may be starting to draw too much
-
current.
-
At this point, we've just completed our first
season of racing in the car and unfortunately
-
I'd say that our results have been a bit of
a mixed bag.
-
We've also broken a fair few parts along
the way.
-
We've also learned a lot and most importantly
we've had a lot of fun.
-
As with any racecar, this is in a constant state
of development, we've got a lot of plans
-
for our off season and we can't wait to
hit the track next season with hopefully
-
a more powerful and more sorted
racecar.
-
If you like free stuff,
and you want to learn more
-
about performance engine
building, and EFI tuning,
-
then we've got a great deal for you.
-
Click the link in the description
of this video to claim your spot
-
to our next free live lesson.
-
You're guaranteed to learn a lot,
and you'll have the chance to ask
-
questions which I'll be answering live.
-
Remember it's 100% free,
so follow the link to claim your spot.