Body - Driver Controls
The driver will be able to operate the vehicle only as well as the driver is able to manipulate the vehicle
controls. Of equal concern is keeping the driver in the driver’s seat, while operating the vehicle.
Factory Seat Belt
The original Geo Storm seat belt has a serious weakness because the lower end is secured via a loop of webbing
around a metal bar which is bolted to the frame rail at the base of the B pillar. The loop of webbing is free
to slide back and forth along the bar, making it very difficult to tighten the seatbelt to hold the driver securely
in the seat. And the movement back and forth of the loop of webbing will eventually saw through the fabric,
especially when exposed to the dirt and grit that is found on the floor of an automobile.
It is highly recommended that the front seat belts be replaced with belts that are the same style as the Stylus
Sedan front seat belts, with a bolt-in style end, preferably with a plastic end and sleeve to protect it.
Racing Harness
The main benefit of a racing harness is keeping the driver securely in the seat and in control of the vehicle.
Pushing a car to 10/10ths will generate enough cornering force to turn everything that is loose in the vehicle
into a projectile. And this includes the passenger and driver. The only think more annoying than having stuff
(or passengers) bang into or fall over onto you, is having to struggle not to fall out of the seat while driving.
Every bit of effort that the driver wastes trying to stay behind the wheel, is effort taken away from the task
of driving the vehicle. A four or five point harness will allow the driver to lash themselves securely into
place, so that they can direct all of their attention and effort to the task of driving.
Floor mount eye bolts can be added to the Geo Storm to allow for installation of a racing harness with clip in
style ends. The special eye bolts are available from racing equipment and seatbelt companies, and are 7/16x20
thread, which just happens to match the US DOT mandated seatbelt lap belt mounts in all automobiles, including
the Storm. Mounting the shoulder harness and anti-submarine belts will require more creativity. Most people
find a mounting point for the shoulder harness around the rear seat hinge mounts or rear seat belt mounts. The
anti-submarine belt usually requires an eye bolt through the front of the horizontal floor brace beneath the
front seat.
Racing Seat
Factory bucket seats are designed for easy ingress and egress, comfort even when wearing a winter coat, and low
side bolsters to prevent wear to the seat fabric.
A tightly fitting racing seat, with high side bolsters and shoulder bolsters, will greatly help hold the driver’s
body in place while driving.
For racing purposes, a reclining seat and floor sliders should be avoided, because they will quickly wear, become
loose, and can break.
Driver position should be considered when making seat mounts. A lower position may be desirable to allow more
clearance for the driver’s helmet to clear the ceiling. This may offer a secondary benefit of allowing more
clearance between the driver’s legs and the steering wheel and steering column. This is important for crash
safety, but also especially important for left-foot-braking providing enough space for the driver’s left knee
when the left foot is placed on the brake pedal. Providing good leg position for operating the floor pedals
is another consideration, and the seat may end up being farther back than the original.
For arm position, refer to the section below covering steering wheel spacers.
Smaller Diameter Steering Wheel
The OEM steering wheel in the Geo Storm is 15 inches in diameter, the same diameter as most standard OEM car
steering wheels. The most common racing steering wheels are 13 5/8 inches in diameter. (This is the same
size used in the Japanese Gemini Type C). The primary reason for a smaller diameter steering wheel is to
decrease the amount of distance that the driver must move their hands in relation to the amount that the wheels
turn (increasing the relative steering ratio without modifying or replacing any difficult or expensive pieces
such as the steering rack or ball joint mounting points]on the spindles). A secondary benefit is that this
provides the driver with more legroom under the wheel, especially for left foot braking.
This will increase steering effort, especially noticeable with manual steering.
With power steering and a racing alignment set with mild toe out both front and rear, this can make the steering
feel very twitchy and even overly sensitive.
Another drawback is that with the tall, stock seat, the rim of the steering wheel will probably block the driver’s
view of the instrument cluster and upper portion of the speedometer and tachometer. This is less of a problem
with a low mounted racing seat.
Mounting an aftermarket steering wheel will require an adapter hub or boss. These have become less common, but
are not impossible to find. The steering shaft spline pattern is the same for all Isuzu made cars (including
the Geo Storm) from the late 1960's through the 1990's. Be aware that any boss listed for Geo Storm and
Suzuki and/or Toyota, will not fit a Geo Storm.
The desirable Momo bosses for the small cars, as was used in the JDM Irmscher and Lotus Tuned cars, were
discontinued many years ago and are impossible to find. But Momo offered more than five different bosses, with
varying offsets for the SUVs, with one remaining available, though they are quite expensive.
In Japan, the most common boss in use in Geminis is the HKB Sports brand. These are made in japan, solid
aluminum, have mounting holes for both common steering wheel bolt patterns (Momo and Nardi), and have a black
plastic accordion trim cover. Another recently introduced brand is Works Bell (WB). These appear identical to
the HKB brand.
Daikei brand offers a steel boss with a textured plastic trim cover that lacks the accordian ribs.
These are available online for purchase from Japanese tuning shops and auction, and they are
occasionally offered on the US auction websites. HKB, WB, and Daikei bosses are much less expensive
than Momo.
Steering Wheel Spacer
Arm reach and position is important for racing. Depending on the type of racing, those requiring more turning,
and endurance racing that will wear down the driver, usually calls for an arm position such that the elbow is
at a right angle when grasping the steering wheel at the 3 o’clock and 9 o’clock positions. This gives the driver
better leverage to turn the wheel.
In such cases, a steering wheel spacer, between the mounting hub and wheel, will move the steering wheel into
the desired position.
One drawback is that this will also move the steering wheel farther away from the turn signal stalk, and the
cowl mounted headlight and wiper switches. It may become necessary to remove a hand from the steering wheel
to operate these switches.
Sparco and Crowder Customizing offer good quality steering wheel spacers in various thicknesses. SRR (Super
Road Racing) brand looks reasonable quality also. Be skeptical of some of the Chinese made spacers, as they
do not appear to be strong enough to stand up to competition use. This is a safety issue, if the spacer breaks
while the vehicle is in motion, there is no way to steer the car. If the spacer has both the Momo and Nardi
bolt patterns, it is a good idea to use 12 bolts of grade 10.9 to hold it to the boss.
Air Bags and Full Face Helmets
In 2004, the FIA and SCCA issued warnings to drivers, stating that a driver wearing a full face helmet will
likely incur head and/or jaw injury in a crash, when the airbag deploys.
An airbag disable switch (available from the vehicle manufacturer with DOT permission/rubber stamped approval
form) is recommended for road use vehicles, with the switch set to the disable position during competition.
Removal of the airbag is recommended for non-road use vehicles used in competition.
Higher Ratio Steering Rack DOHC vs. SOHC ratios
There are two different power steering rack ratios in Geo Storms. The Base/SOHC Storm (and all of the Standard
and Lotus equipped Isuzu sister cars) have a 16.1 : 1 steering ratio. The Storm GSI (and Japanese Irmscher
Gemini sister cars) have a 14.3 : 1 steering ratio. The lower number (higher ratio) is more desirable for
racing, because the wheels turn more quickly for less steering wheel movement by the driver (the movement is
faster).
For a SOHC (and the USDM FWD Isuzu sister cars), an upgrade would be as simple as swapping in a steering rack
from a DOHC car.
Manual Steering Rack – A Bad Idea
The parts catalogs list a manual steering rack was available for the Geo Storm, though almost never seen. The
primary drawback would be that the ratio is extremely slow, 20 : 1 compared to 16.1 : 1 in the SOHC (and Isuzu
sister cars) and 14.6 : 1 in the DOHC. This is to make the steering effort of the manual steering rack
“acceptable” for road use. Bear in mind that these cars are front wheel drive, have 2/3 of the vehicle weight
on the front axle, and were designed to be used with the originally equipped, lowest trim level, narrow 175
tread width tires. Put some wide 205 width, sticky performance tires on the front, and the steering effort
is just too high and movement too slow for the quick actions needed for racing. For those who think they are
Arnold Schwarzenegger or Lou Ferrigno in their prime, carefully box and store all of the original power
steering system, the pump, pipes, and rack, to be reinstalled in the vehicle after a few weeks or months of
aching upper body and shoulder pain. And make sure not to loose any of the brackets, bushings, and clips,
because replacements are nearly impossible to find.
From a performance standpoint, in any use requiring turning, the car will be faster with power steering, than
with manual steering.
Converting Power Steering to Manual by Looping the Power Steering Lines
This is a particularly ill-advised action. The belief is that by hooking the pressurized line to the return
lines of a power steering rack, then there will be no added effort to move the rack, and it will function as
a manual rack. The reality is that the drive unit of the power steering system is built into the base of the
pinion gear, and it requires a great deal of effort to turn the gear along with all of the power mechanism (the
pump supplies 500+ PSI when the wheel is straight, and 1,200 PSI when the wheel is turned to its limits,
that’s a lot of force). This is combined with the higher ratio of the power rack (16.1 : 1 or 14.3 : 1). The
driver effort to turn the wheel will be excessive, and significantly more than the effort to turn the factory
manual steering rack.
Again, from a performance standpoint, in any use requiring turning, the car will be faster with power steering,
than with manual steering, especially manual steering done wrong.
Pedal Covers
Pedal covers became a fashion statement in the 90’s, but purpose made covers will improve driver control. The
original rubber covers are slippery to a wet shoe sole, and after 20 years, likely worn smooth enough to be
slippery to a dry shoe sole. An aluminum pedal cover with a raised tread pattern will drastically enhance grip
both dry and wet.
In addition to this, oversized pedal covers improve the spacing of the pedals. The stock pedal arrangement
spaces the pedals far apart, so that the driver will not inadvertently hit the wrong pedal, or more than one
pedal at a time, by accident. Racing pedal covers are oversized, reducing the space between the pedals, making
it possible to heel-toe the accelerator and brake with the right foot, which is needed for heel-toe technique,
rev matching during downshifting, and using the right foot on the accelerator and instep on the brake pedal
for a pseudo-left-foot-braking-style technique.
Short Throw Shifter
Reducing shifter throw is relatively misunderstood. Uninformed drivers think this is all about speed, and that
shorter-equals-better. Their desire is for a shift throw that they term as “like a flip/flick of the wrist”.
The reality is that the effort needed to move the gear selector mechanism from one gear to the next, is
directly related to the distance the lever must move. A gear lever with a throw of one or two inches, will
quickly cause pain to the driver’s arm, and make them regret ever wishing for something so foolish.
However, reducing shift lever travel by a much smaller percentage, can provide some benefit, by giving the gear
change a more solid feel, and by keeping the drivers elbow from hitting the seat side bolster during shifts
into 2nd, 4th, and reverse. Reducing the shift lever throw from 6 inches to 4 ½ - 5 inches is reasonable and
beneficial, and provides some additional range to adjust the lever assembly to re-center the lever and move the
range of throw fore-aft or left-right if desired. This isn’t any faster, but gives a more assertive feel when
operating the vehicle, and reduces the number of missed shifts.
Raising the Shift Lever Assembly
The original gear lever position in the Geo Storm, and most cars, is dictated more by appearance, providing an
unobstructed view of the dashboard, and access to the center console buttons, than actual operation of the
vehicle. For function, raising the gear lever assembly so that the knob is roughly the same height as the center
of the steering wheel, will greatly enhance driver control. This reduces the distance the right hand must travel,
between the wheel and gear lever while executing a shift, and gives the controls a much more intuitive feel.
Raising the shift lever assembly can be accomplished by making a mounting bracket spacer to fit between the
assembly and the floor pan that the assembly mounts.
Moving the Shift Lever Assembly Forward
In the event that the driver's elbow is hitting the seat side bolster during shifts into 2nd, 4th, and reverse,
the best solution is to move the stick shift assembly forward, to provide more space between the shifter and
the seat.
As described above, this is accomplished by making a bracket to fit between the shift assembly, and the floor
pan where the assembly mounts. However, in this case, the bracket would offset forward, instead of upward.
Care should be taken to allow adequate space between the shift lever in 1st, 3rd, and 5th gear positions, and
the dashboard. An inch forward makes a big difference in the clearance and feel.
Many find that this moves the shift lever into a better and more intuitive position for controlling the vehicle.
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