Building the Ultimate GT1
By: Rich Vecchio
Date: May 16, 2015
The Ultimate GT1 just might be the Toyota GT-One. Although
the Tamiya kit is a rather complex build, the slot car version looks and runs
great! For those of you not inclined to read my long winded dissertation, images
of the model and its one to one counterpart are shown below. The salient points
are summarized in the section entitled “Summary” below. For those suffering
from insomnia, plowing through the many sections jam packed with detail might lead
to “safe and restful sleep”. Who needs Sominex anyway? The titles of each
section and a brief description of their content are shown in the table below.
|
Section Title |
Content |
|
Summary |
Specifications
and final test results for the Toyota GT-One build |
|
Background |
Development
of our True Scale GT1 class including configurations, improvements over time
and popular body selections. |
|
The Build |
Challenges
encountered and overcome building the Toyota GT-One (and there were many, I
might add). Read this section in order
to avoid aggravation if one intends to convert the static model kit into a
slot car. |
|
Statistics |
Analysis
and historical results aggregated by race course, make and model for True
Scale GT1 |
|
History of the Toyota GT-One |
Specifications
of the actual race car and a short history of Toyota’s obsession with
winning the penultimate endurance
race, Le Mans |
Summary
How can lap times be improved in a well-developed class
that specifies a production chassis, sealed motor and a well-known pan
configuration? The answer might be body selection. The answer might be the Toyota
GT-One.
The basis for this latest build is as follows.
·
Tamiya 1/24 Toyota GT-One plastic model kit
·
Scholer Pantera chassis fitted with new and
wider side pans including a notched edge (The chassis was formerly used on my
Porsche 962)
·
Hawk 7 motor
The Toyota GT-One made its racing debut on 5/14/2015 at
Electron Raceway. The GT-One handled like a dream. The car seldom de-slotted
and was perfectly balanced, neither too loose nor too tight. The Toyota now
holds the track record for laps (91.3) and the record for fast lap at 4.891. I
think the GT-One is one of the best, if not the best body to run in our GT1
class. Both the front and rear track are much wider than the prior record
holding Porsche 962 while the height and weight of both bodies are quite
similar.
Background
Since its inception several years ago, True Scale GT1 has
developed into one of our most competitive classes. Rules for this class
dictate a Scholer or Plafit production chassis and a sealed Falcon 7 or Hawk 7 motor.
All competitors utilize a similar custom front and side pan configuration designed
to improve handling. In addition, the GT1 and Group C bodies specified for this
class are very low, and are characterized by a relatively long wheelbase. All
of these factors facilitate very fast and very close racing. The latest
stepwise improvement in lap times can be attributed to the addition of the Hawk
7 motor as an optional power plant. The Hawk has more snap and better brakes
than the Falcon, yielding improvements in lap times of .1 seconds or more.
With such a well-developed class, how can lap times and
handling characteristics be further improved?
The answer could be in body selection. Although the Ferrari Enzo has dominated
the class in terms of total entries and podium finishes, other bodies such as
the Porsche 962, Nissan R390 and Jaguar XJR12 have achieved a modicum of success
(For more detail, read the section entitled “Statistics” below). Could another
body be a better alternative?
In the winter of 2014 I had the pleasure of racing with
the Arizona Garage Racing club (AZGR). One of the track owners displayed a
great looking Toyota GT-One mounted on an H&R chassis. The car’s shape and
design was, I believe, way ahead of its time. Recently, while surfing the
internet, I found the model for a reasonable price and immediately placed an
order. While waiting for it to arrive, I did some research regarding the
history of the actual race car. Toyota’s GT-One program was specifically aimed
at winning the penultimate endurance race, Le Mans. The effort was, however, short
lived, lasting only two seasons (1998 and 1999). Although the GT-One showed
great potential, it failed to win the premier event. In 2000, the program was
abandoned in favor of an all-out Formula 1 effort. For more information on the
GT-One program see the section entitled “History of the Toyota GT-One” below.
The
Build
Tamiya makes some of the most detailed static models on
the planet and the Toyota GT-One is no exception. Two kits are available, but I
would not suggest purchasing the “Full View” model. Box art for both kits are
shown below.
Unfortunately, some of the detail as well as the race car
design itself would present several challenges. Some of these are summarized
below.
·
In the actual race car, the driver’s tub is a
part of the aerodynamic design and is in full view from the large openings in
each of the slab sides of the car. Using the tub as part of a slot car build was
a non-starter because of clearance and weight considerations. Instead, .020” sheet
styrene was used to cover the openings.
·
Because the rear deck is so low in spots, the
spur gear did not clear the bodywork. A small rectangular cut out resolved this
problem. If an inline rather than an anglewinder or sidewinder chassis
configuration is used, the cut-out might not be necessary.
·
The wheel openings are very tall and provide
ample clearance for the ProTrack tires. However, the rear fenders are too
narrow to accommodate the ProTrack tire width. Small cut outs in the inner
portion of the rear fender bodywork solved the problem.
·
The body is constructed from relatively thin
plastic. This coupled with large wheel openings, leaves the front end
vulnerable to impact. In order to bolster strength and rigidity, carbon fiber
mesh was affixed to the inner portion of the front wheel wells. In addition,
the kit has a belly pan that covers the front end. The pan may be affixed and then cut to clear
the guide flag, again to bolster rigidity.
·
There are two relatively small plastic pieces
that extend the bodywork into the inner front wheel wells. These pieces must be
trimmed to avoid interference with the inner portion of the front wheels.
·
The rear wing assembly consists of three
pieces including two uprights and the wing itself. The assembly then attaches
directly to the rear bodywork. As such, it is subject to damage from a rear end
collision. To insure a very strong bond, plastic welder was used to attach both
the wing and its uprights.
·
The outer skin of the body consists of two
major and several minor parts. The rear deck of the static model is hinged and
opens to display the mid-engine and rear suspension. For the slot car version
of the model, plastic welder was used to mate the rear deck to the front
section of the model.
·
The nose of the race car and the aerodynamic
air-intake on the roof are white while the rest of the outer skin is red. I had hoped for white decals. Instead, masks were provided for a two-tone
paint job. After the fact, I noticed two
small masks that looked like “crowns”. Nowhere in the instructions were these shown. Nowhere on the box-art was the true color
scheme reflected. However, images of the actual race car (see images in the
section entitled “History of the Toyota GT-One”) show that one of the “crowns”
should have been used as an extension of the large front mask and the other
should have been used on the roof air-intake. The only mask that I used worked
quite well but the two tone paint job delayed the model’s completion.
·
Two small aerodynamic tabs on the leading
edge of the front fender are weak. In testing one broke off in a not to violent
wreck. One might think about filing the tabs off prior to painting.
·
The model kit came with two sets of high
quality decals: The number 1 car sponsored by Zent and the number 3 car
sponsored by Esso. Both are replicas of entries in the 1999 Le Mans race. The
Zent car qualified first on the grid but did not finish. The Esso car started
eighth on the grid and finished second. I
selected the Esso decal set.
My GT-One project began with a Scholer Pantera chassis formerly
used on my somewhat successful 962. First, I replaced the Falcon 7 motor with a
Hawk 7 power plant. Second, I was never happy with the side pans on this
chassis. They were simply too narrow. New side pans were fabricated from one
inch wide, .062 inch thick brass plate with a small notch machined into the
outer edge to facilitate body mounting. The wheelbase of the GT-One is ever so
slightly longer than the Porsche 962; therefore, the front axle required a very
slight relocation. The car ran so well in initial testing that I decided to
postpone consideration of fabricating a new and larger front pan.
The wait was excruciating while the GT-One received a two-tone
paint job, decals and a few coats of Future. Finally, the finished product was
ready for testing. Subjectively, I felt
that the GT-One handled better than the 962. The Porsche seemed to be a bit “tail
happy”. Below are a few images of the finished product.
Statistics
Our GT1 class includes Group C and GT1 plastic model
bodies, some of which are quite expensive and hard to find. In an attempt to
keep costs down, we allow wide sports cars such as the Ferrari Enzo and La
Ferrari to run in this class as well. Many competitors have migrated to the
Enzo. In fact nearly two thirds of all GT1 entries have been Enzos. However,
other makes/models have achieved a modicum of success.
Initially, GT1 events were held at Electron Raceway,
however, in time, the class was added to the mix at STR. Electron Raceway and
STR are very different race courses. STR is characterized by very tight turns
and long straights. STR also has a “hump” on the pit straight. Electron Raceway
is characterized by sweeping turns and short straights. As the saying goes,
“different horses for different courses”. It appears that this saying applies to
Electron Raceway and STR. Therefore, historical results have been aggregated by
race course as well as make and model. Results are shown in the tables below. Race
data is provided from my Slot Car Database and includes results from July 2013
through May 2015. My interpretation of the data is presented in bullet point
form below.
STR Headlines
·
The Ferrari Enzo has been the dominant force
at STR
o
Only the Enzo has turned a fast lap of under
5.0 seconds (Ron turned a 4.936 with his red Enzo and Bob turned a 4.938 with
his black/yellow Enzo)
o
The Enzo holds the record for highest lap
count at 92.6
o
Out of 10 races at STR, Enzos won 9 times, finished
second 7 times and third 7 times
·
The only other car to win GT1 at STR was the
Jaguar XJR12
·
The only other cars to finish on the podium
at STR were:
o
Nissan R390 – 2nd
o
Porsche 962 – 3rd
Electron Raceway Headlines
·
The Toyota GT-One now holds the record for
high lap total (91.3) and fastest lap (4.891)
·
The Porsche 962 has been a formidable
competitor at Electron Raceway
o
The 962 is one of only three cars to break
the 5 second barrier with a fast lap of 4.991
o
The 962 notched the highest number of wins
(7).
o
The 962 is third in total lap count at 90.0
·
The Ferrari Enzo is a very competitive ride
as well.
o
The Enzo is only one of three cars to break
the 5 second barrier with a fast lap time of 4.994.
o
The Enzo finished first 4 times and second 8
times
·
Jaguar XJR12
o
In its six outings, the Jaguar XJR12 managed
to notch a single win, finished second once and third once.
·
The only other cars to finish on the podium
at Electron Raceway were:
o
Corvette C5R – 2nd
o
Jaguar XKR GT2 – 3rd
Other considerations (Both Tracks)
·
Jack’s Nissan R390 is a very good ride,
finishing second in the last GT1 contest at STR
·
Jack’s Porsche GT1 has never been raced but
seems to be very fast in practice
·
Since converting to a Hawk motor, James’
Jaguar XJR12 can run with the best in class
|
GT1
Race Results STR |
||||||
|
Make/Model |
Fast Lap/Driver |
High Lap Total/Driver |
Best Finish |
Number of Outings |
Wins |
Winning Percentage |
|
Ferrari Enzo |
4.936/Ron |
92.6/Bob |
1st |
10 |
9 |
90.0% |
|
Nissan R390 |
5.045/Jack |
90.3/Jack |
2nd |
4 |
0 |
0.00% |
|
Jaguar XJR12 |
5.092/James |
87.5/James |
1st |
9 |
1 |
11.1% |
|
Porsche 962 |
5.107/Rich |
87.4/Rich |
3rd |
2 |
0 |
0.00% |
|
La Ferrari |
5.215/Ron |
84.8/Ron |
5th |
1 |
0 |
0.00% |
|
Porsche GT1 |
5.496/Ron |
77.1/Terry |
5th |
3 |
0 |
0.00% |
|
Nissan R89C |
5.777/Nick |
74.4/Nick |
7th |
1 |
0 |
0.00% |
|
GT1 Race Results Electron Raceway |
||||||
|
Make/Model |
Fast Lap/Driver |
High Lap Total/Driver |
Best Finish |
Number of Outings |
Wins |
Winning Percentage |
|
Toyota GT-One |
4.891/Rich |
91.3/Rich |
1st |
1 |
1 |
100.0% |
|
Porsche 962 |
4.991/Rich |
90.0/Rich |
1st |
9 |
7 |
77.8% |
|
Ferrari Enzo |
4.994/Bob |
90.5/Rich |
1st |
14 |
4 |
28.6% |
|
Jaguar XJR12 |
5.098/James |
88.9/James |
1st |
6 |
1 |
16.7% |
|
Jag. XKR GT2 |
5.166/Rich |
83.3/Rich |
3rd |
1 |
0 |
0.0% |
|
Nissan R390 |
5.210/Jack |
84.4/Jack |
4th |
1 |
0 |
0.0% |
|
Corvette C5R |
5.285/Jack |
82.0/Jack |
2nd |
1 |
0 |
0.0% |
|
La Ferrari
|
5.343/Ron |
82.0/Ron |
4th |
1 |
0 |
0.0% |
Images of some of our GT1 rides are shown below.
History
of the Toyota GT-One
Throughout its history in Group C, Toyota never achieved
its goal of a Le Mans win. A change in the GT1 class homologation requirements
for 1998 offered Toyota a simple path back to Le Mans without the requirement of
constructing 25 road-going examples. The new rules called for only a single
street legal copy. After the rule change was announced, Toyota embarked on an ambitious
program specifically aimed at winning the pinnacle of endurance races, Le Mans.
The cutting edge machine was dubbed the TS020 aka the Toyota GT-One.
The car was built around a carbon-fiber monocot with an
aluminum honeycomb core, which used the engine as a stressed member. While the
chassis was designed by Toyota, it was actually manufactured by specialists
Dallara in Italy. The suspension included double wishbones with push-rod
actuated springs and dampers on all four corners. Carbon-ceramic brakes were
also used all around.
The motor selected as the basis for the GT-One was an
already existing power plant used in Toyota’s Group C entries – a purpose built
3.6 liter V8 with four valves per cylinder and equipped with twin turbochargers.
The motor was redesigned for the GT-One; height and weight were reduced
improving fuel economy, boosting power and changing the rev range. In the end,
the motor produced 600 horsepower. Not bad for a car weighing in at just under
2000 pounds.
Since the car was intended to be run only at Le Mans, the
design focused on reducing aerodynamic drag to the very minimum facilitating
the highest speeds possible on the long straight sections of the race course. As
such, it featured a minimal frontal area and a relatively long tail. A design
feature that particularly stood out was the front wheel-well cut-out, intended
to prevent pressure from building up inside the wheel-well. A single, small,
aerodynamic air-intake was designed for the roof, again with drag-reduction in
mind.
The initial layout was completed on the computer and the
shape was further refined in a wind-tunnel. Production of the GT-One commenced
in October of 1997. Testing began in December and three cars were ready for an
assault on Le Mans in May of 1998. In addition, two road-going cars were built
to meet the homologation requirements. Neither road-going car was ever sold. One was put into a museum in Japan; the other is
displayed at Toyota Motorsport in Cologne, Germany.
Toyota fielded a team of
three cars for the 1998 Le Mans contest. The best of the three Toyota GT-Ones
qualified second. Unfortunately, this car was involved in an accident early on
in the race pinning Toyota’s hopes on its remaining two GT-Ones. The better of
the two ran second until the final hour when it succumbed to a transmission
failure. The remaining GT-One ended up a disappointing ninth.
Not to be deterred, Toyota refined the GT-One design and
entered a three car team in the 1999 Le Mans race. GT-Ones qualified an
encouraging first, second and eighth. Unfortunately, tire problems and
relatively high fuel consumption doomed the 1999 effort. Some have reported
that the Michelin tire failures were a result of sharp gravel that made its way
onto the racing surface. Unfortunately, tire failure on the Toyota GT-One often
resulted in damage to the mechanical linkage rendering the cars inoperable. That
is exactly what happened after 90 laps when the first GT-One was lost due to an
explosive tire puncture. About half way through the race, a second GT-One tire
puncture led to a high speed accident which destroyed the car. The remaining
GT-One soldiered on, running near the top of the field. In the final hours of
the race, the remaining GT-One was in second place and closing on the lead BMW.
After all of the hard work and disappointment endured for over a period of more
than two years, there was hope that, at last, the GT-One would conquer Le Mans.
Then, with a bang, another tire failure led to another disappointment. The
remaining GT-One was, however, able to limp back to the pits where a new set of
tires was installed. The unfortunate incident relegated the GT-One to second
place, dashing Toyota’s hopes for a Le Mans victory. After the 1999 season,
Toyota withdrew from sports car endurance racing to concentrate its efforts on
Formula 1, thus ending the era of the GT-One. Below are images of the 1998 and 1999
team as well as the road going version.
