The Kobra 427 SC Chassis was designed from the ground up to handle the
power that most owners expect. The original Cobra’s narrow ladder frame was not
torsionally stiff enough to handle the power. So we changed the chassis –
for the better.
We have designed the chassis in round section tubes as per the original
vehicle. However, the main rails are on wider centres ( 680 mm ) than the
originals which greatly increases the torsional strength – the torsional
strength of a structure is proportional to the square of the distance between
the tubes. ( This is one of Newton’s laws of physics, some so called
manufactures try to defy these laws of physics which is why their vehicles have
such disastrous handling.)
We have also incorporated a substantial X brace between the two main
tubes to further increase the torsional strength of the chassis.

As you can see, we use round section (100 dia ) steel for the main rails. As
well as giving the chassis a more authentic appearance, it substantially adds to
it’s torsional strength. What can not be seen is the material itself. We use high
tensile steel for all the components in the chassis, this increases it’s
strength even further and allows us to use thinner sections – the result is a
chassis that is both stronger and lighter. The tube used has a tensile
strength of 690MPa, square tube has a typical tensile strength of 350MPa !!!
We also have duplicated the original cars front cross brace for visual
authenticity & to further improve the torsional rigidity of the vehicle.
A tubular & pressed steel sub-structure is welded directly to the main rails and
extends completely around the passenger compartment. This structure provides not
only the mounting areas for the body structure, door hinges, latches and
dashboard, but also incorporates side impact protection.
Manufacturing a vehicle with this degree of integration takes a little
longer, but you achieve a much stiffer overall structure. Our chassis has
been measured at almost 15,000 Nm/deg of twist. Far stronger than any other.
This is the reason why our vehicles handle so well.
Our suspension pick up points feed loads directly into the chassis,
minimising bending moments. Large reinforcements are designed in. The chassis
allows the suspension to take full advantage of today’s advanced tyre
technology.
Our optional roll bar is actually functional, bolting directly to
mounts on the chassis. Some replica’s bars are just for show, bolting to the
fibreglass.
A little crash protection:
Our chassis has three stages of impact dissipation.
The bumpers will collapse progressively.
When the the front bumpers are hit hard enough, the chassis is designed to
have controlled shear on the mounting brackets.
The extensions in the front of the chassis that carry the bumpers and
radiator are designed to distort progressively up and back under severe impact.
The rear extensions that carry the bumpers and fuel tank, are designed to
distort progressively forward and downwards.
This means that if the vehicle were to be involved in an accident, it is
easier to repair because the main chassis does not suffer distortion.
This has been proven several times with altercations with concrete barriers
at race tracks!
FRONT SUSPENSION
The Kobra uses independent front suspension in a non-parallel, unequal length
configuration. The correct camber change and anti- dive have been designed
into the geometry. Because we started with a clean design slate, we were
able to avoid the problems associated with using a donor vehicle’s geometry.
In other words, it’s correct for the vehicle, not a compromise.
The tubular arms have been designed to minimise weight & hence reduce the
unsprung weight of the vehicle.
Camber & castor changes can be performed quickly & easily if the vehicle is
to be used for both circuit & road. You can achieve up to 5 deg negative camber!
Because we have designed the suspension around "production" parts, a huge
range of brake options are available.
We have allowed more than 150mm of wheel travel.
You will never use the bump stops on this car!
REAR SUSPENSION
The Kobra uses independent rear suspension - upper & lower lateral links,
twin trailing links, toe link. The correct camber change and anti-squat have been designed
into the geometry. Like the front it is correct for the vehicle. The roll
centre has been designed to optimise the vehicle's handling.
Again, as per the front we have designed it to use "production" components.
In this case the GMH VE Commodore unit ( made by ZF )
DRIVE TRAIN
Due to the regulations, a current series engine with, all it’s associated
pollution equipment, must be used. The 6.0ltr all alloy V8 is the best option.
Our chassis will accept the following transmissions without modifications:
BTR T-5
BTR T –56
Tremec 5 & 6 speeds
BRAKES
Our standard brakes at the front are based on the the VZ Commodore components
– 328 x 28 ventilated discs & two piston callipers.
At the rear, the standard GMH ventilatd discs ( 324 x 22 ) and two piston callipers.
Hydraulics: twin master cylinders with a balance bar – just like the
original!
THE OPTIONS
If you are not mechanically inclined or are short of time, we can do the
labour or supply anything to help make your assembly job easier. We will also
make every attempt to accommodate special requests. Many people choose to have
us create a "roller" for them. We will install the suspension, steering and
breaking systems into a body/chassis unit at the factory. We also have a painter
who does near-show quality jobs at a reasonable price – and on time! If you
visit, you’ll see the excellent job he does.
We keep in close contact with all our customers, and any problems are quickly
resolved.
Good service is inseparable from a quality product.
We know that a satisfied customer is our best salesperson. Although others
may be initially cheaper to buy, they are not necessarily cheaper to build. All
Cobra replica’s need the same basic parts to assemble. If they don’t come with
the kit you still have to purchase or fabricate them later. No other Cobra
replica offers the bottom line value of a Classic Revival. When you consider the
high resale value of our products, the ID 427 SC becomes a great buy.