A vehicle’s chassis is the main structures of the vehicle, where all other components are assembled to the frame. Each vehicle’s attribute were being designed to satisfy the requirements of a desired group of end users.


Being the most out of street vehicles, normal passenger cars were being formed for a few common goals and comfort is one of them. In order to achieve this, a set of street use suspension and soft spring rate will be fitted. While maintaining the level of comfort, the vehicle would be sacrificing its ride handling. The vehicle tends to increase in body roll especially during emergency stops which contribute more forces to the front, resulting in poor steering response, stopping power and even result in accidents.



Strut Bars and Chassis Strengthening Technology:

If you’re serious about your car’s handling performance, you will first be looking at lowering the suspension. In most cases, unless you’re a complete gear head, this will be more than adequate. However, if you are a keen driver, you will be able to get far better handling out of your car by fitting a couple of other accessories to it. The first thing you should look at is a strut brace. 

When you corner, the whole car’s chassis is twisting slightly. In the front (and perhaps at the back, but not so often) the suspension pillars will be moving relative to each other because there’s no direct physical link between them. They are connected via the car body, which can flex depending on its stiffness. 

A strut brace bolts across the top of the engine to the tops of the two suspension posts and makes that direct physical contact. The result is that the whole front suspension setup becomes a lot more rigid and there will be virtually no movement relative to each side. In effect, you’re adding the fourth side to the open box created by the sub-frame and the two suspension pillars.

Is there a need to have our vehicle chassis strengthened?

The chassis of the car is the part which experiences the most of the abuse from the driver. It is particularly due to the weight transfer of the vehicle body during fast cornering, hard braking or hard acceleration.

In some instances, the weight transfer during cornering may cause one side of the vehicle to experience as much as 3 times more force than the other side of the vehicle, causing enormous chassis flex/ vehicle body deformity and twist, consequently causing tires to lose grip. Deformity and twisting of the vehicle chassis during cornering may cause negative handling traits such as under-steering and over-steering.




The front wheels are likely to slip towards outside of the turn angle, driver can solve it by turning a little more slightly but the handling is reduced, vehicle’s behavior is less predictable and tires are likely to worn out faster. Under-steer often occurs in front wheel drive layout vehicles.



The rear wheels are likely to slide towards the outside of the turn more than the front. The driver must correct by steering away from the corner otherwise the vehicle will tend to spin when it has been pushed to its limit. Oversteer often occurs in rear wheel drive layout vehicles.


  1. As most modern cars go, car manufacturers employ the FF (Front engine, Front wheel drive) setup for improving driver and passenger safety. The natural behavior of an FF car is to have a slight understeer, due to its heavier front end. Understeer happens when the front wheels lose their traction and won’t turn any sharper, even when the steering is being corrected to turn the car more. This will cause the car to go wide instead of following the line. Understeer can be corrected by stiffening the rear end of the vehicle by adding a Rear Strut Bar and a Rear Anti Roll Bar.
  2. Oversteer is when the rear tires lose grip and causing the rear end of the vehicle slides out of a corner. This phenomenon happens particularly to FR (Front engine, Rear wheel drive) or RR (Rear engine, Rear wheel drive) cars. Oversteer can be corrected by stiffening the front end of the vehicle by adding Front Strut Bars and Front Anti Roll Bars.



When any of the wheels loses contact with the road surface, there will be a deviate in handling; each of the suspension system should keep all wheels on the road surface in spite of hard cornering and in change of steering position. It’s always pleasing that that car can be set for a tiny amount of understeer so that it responds predictably to a turn of a steering wheel and the rear wheels to have a smaller dip angle than the front wheels. However this may not be achievable at all times due to the vehicle load, road condition, weather, speed and this consumes excessive time for the driver to adopt.




Part of the shock of impact transfer to the chassis, causing wheel house and lower arm deforming.




Equip with the Ultra Racing’s strut bar and lower arm bar, both side shock of impact will be neutralized.




The weight transfer and force gathering on one side, causing unstable  handling and increasing body roll.




The force will spread out by Ultra Racing’s strut bar and lower arm bar, stabilize the car and provide solid handling.




The joint between A-pillar and front chassis will be push and twist by the greater shock of impact and drag force, causing damage on chassis.




Ultra Racing’s Fender bar will spread out the force and strengthen the section, prevent further damage and offer stable handling. Recommend for user of sport absorber.




On uneven / bumpy road, center section chassis will have different level of body flex cause by the weight transfer between front and rear.




Ultra Racing’s side lower bar will stabilize the weight transfer between front and rear, it can also minimize the damage from side impact.




When turning in corner, the weight transfer will make the car sway a side, causing body roll and more difficult to turn in to a corner, weaken the steering respond.




The upgrade version of Ultra Racing’s anti roll bar will be more effectively preventing the car sway a side at cornering, greatly reduce body roll and high stability in cornering.



In order to reach the desired performance of Ultra Racing products, we constantly monitor the quality of our bracing, not only during the production stage, but also conduct strict performance testing afterwards.

During the development phase of Ultra Racing bars, we ensure the products are in accordance to our design and development philosophy. We conduct real on-road performance test as well as on-track testing. In order to obtain data, we also invented three testing jigs, namely Bending Test Jig, Torsion Test and Flex Test Jig.

These jigs are used to test the performance of our products on a continuous basis.

The strut bar is bolted to the jig to simulate the actual situation on the vehicle chassis. For torsion test jig, torque is applied to one side of the bar, and the amount of twist is recorded. Torque used was calculated and fixed at 6.6kg/m.

For compression test jig, forces are applied along both sides of the bar. Maximum compression force is recorded to study the structure of various kind of designs that the bar can withstand under different driving conditions including impact simulating an accident. We use a hydraulic pump to compress at set pressures and record the results

For flex test jig, torques are applied on the ends of the bars to simulate the performance of the bar under chassis flex conditions. Torque used for the experiment is fixed at 8kg/m.





Brand : UR (Civic EK 2 points)

Bracket : Non Adjustable

Bracket thickness : 4MM

Weight : 3.30LBS (1.5 KG)

Compression Impact : 3MM (100 psi)



Brand : ??? (Civic EK 2 points)

Bracket : Adjustable Bracket thickness : 4MM

Weight : 3.08LBS (1.4 KG)

Compression Impact : 70MM (100 psi) 




Brand : UR (Civic EK 2 points)

Bracket : Non Adjustable

Bracket thickness : 4MM Weight : 3.30LBS (1.5 KG)

Flex : 50MM (8 kg/m)



Brand : ?? (Civic EK 2 points)

Bracket : Adjustable

Bracket thickness : 4mm

Weight : 3.45LBS (1.4 KG)

Flex : More then it should 



Brand : UR (Subaru Forester 2 points)

Bracket : Non Adjustable

Bracket thickness : 4MM

Weight : 3.96LBS (1.8 KG)

Torsion : 47MM 


Brand : ?? (Subaru Forester 2 points)

Bracket : Adjustable

Bracket thickness : 4MM

Weight : 4.4LBS (2.0 KG)

Torsion : 85mm


Every materials used are carefully selected to ensure the best performance and safety. The brackets are made of 4MM to 5MM steel plates, while the hollow steel tubes and oval tubes are of 1.2MM to 1.6MM thickness. These materials are selected to ensure the bars are rigid and strong to maintain constant geometry at all times, yet safe enough to crumble during an impact for safety reason

All our raw materials has been made and tested with satisfactory result.

To achieve safe condition, the displacement must be less than the thickness of the material which is below 2mm.

Therefore, the bar is in SAFE condition.


MILL / TEST CERTIFICATE (Chemical Composition)

JIS 3101 SS 400 (Japan International Standard)

JIS G 3141 SPCC SD (Japan International Standard)

ASTM A 500 Grade A (American US Standard)

BS 1387 ( British Standard)



Why We Use Steel Instead of Aluminum?

First, steel is stronger than aluminum for the same size and thickness. In order for aluminum alloys to be at least the same strength as steel, it has to be at least double the thickness (Steel 4MM = Aluminum 8MM).

When that happens, weight saving is not so apparent anymore. Of course there are also exotic materials and alloys that can match the strengths of steel, but the cost are astronomically high and therefore not very cost effective to bring into mass production.