Project Scion TC Part Two, Chassis and Cage Construction Details


Technosquare Scion TC cage
Technosquare Scion TC cage
After measuring, the tubing is cut using a chop saw and notched using a hole saw and mitering fixture

Proper seating is also important for a race car.  A lot of what a driver feels is communicated to his body though the seat.  A proper seat is comfortable and supportive which helps reduce driver fatigue by holding the body in place under cornering load.  It is much better to let the seat hold you in instead of trying to brace yourself with your arms and feet while trying to steer.  A properly designed seat is also an important piece of safety equipment as well that helps absorb the shock of a bad impact while helping distribute the force of a crash over a larger area of the body.

Technosquare Scion TC cage
A long ruler and a level is used to mark the position of the tube

We selected a pair of Recaro Pole Position FIA approved seats for Project Scion TC.  The seats are constructed using a sturdy but flexible fiberglass reinforced plastic material called GRP. The FIA approval means that they have been tested to FIA’s stringent impact standards. For racing use it is imperative that one looks for the FIA label to insure that you are getting a seat that is tested to withstand the stress of a severe accident.  We have seen seats fail in racing accidents with tragic results so seating is not the place for false economy or making a JDM fashion statement.  In addition to an FIA approval, the Pole Position seat is a feathery 11 kilograms in weight.  This is pretty good as most FIA seats tend to be heavier than unapproved seats.  Another advantage that FIA approved seat have is that they have properties of controlled flex.  This flex helps absorb some of the shock of impact protecting the driver’s body.

Technosquare Scion TC cage
Technosquare Scion TC cage
The tube is held in a fixture that hold the correct angle then notched using a fixture that hold s drill with a hole saw
Technosquare Scion TC cage
Checking postion with a ruler and level
Technosquare Scion TC cage

Finaly the tube is tack welded in place

Technosquare Scion TC cage

 Technosquare Scion TC cage
 This stout brace triangulates the strut towers and the firewall

The best seat in the world won’t help you in an accident if it is improperly mounted.  Technosquare mounted the seat to the Scion’s chassis using FIA approved seat sliders.  FIA sliders have double locking mechanisms, one in each rail to assure that they won’t move in an accident.  The seat was mounted as low and as in board as possible to get the driver as far away from the roll cage and the side of the car as possible to afford more protection for the driver.  The sliders were mounted on the modified stock front mount and a new rear crossmember was fabricated for the rear mounts out of square section tubing with generous plates to make sure that the mounting point was strong enough.


Technosquare Scion TC cage
Technosquare Scion TC cage
NASA rules give penalty points if the cage extends through the firewall so this clever brace was built that bolts the cage to the triangulated brace through the firewall

To further stiffen the chassis, a brace was built from light but stout aluminum tubing that ties the shock towers to the firewall.  Since NASA gives penalty points for having a rollcage that penetrates the firewall, another brace from the cage bolts to the strut tower brace through the firewall to give extra stiffness while staying withing the rules.

Now that our chassis is complete, we will turn our attention to other areas of the car in the next segments of Project Scion TC


Safety Equipment Standards 

Roll cage fabrication

Carbon fiber hood

Pole Position seats

Toyota Racing Development
Parts Support, Limited Slip Differential

The Progress Group
Coilover suspension, Adjustable racing antisway bars

Carbon fiber roof

DC Sports
Headers, exhaust

Cold Air Intake

Nitto Tire North America
NT01 Tires

Brake pads

Tire Rack

Dezod Motorsports
Engine development, Scion tC performance parts

America’s Tire
Tire mounting/balance support

Safety equipment

turn3 Creative

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