1200 sedan struts

 Adjustable platforms with King springs and all Bilstein inside.

  CANISTER STRUT PROJECT

A current Datrats project is manufacture of custom canister struts. These are a high oil volume (external reservoir) shock that is adapted to a large diameter strut for rally or circuit work. It can be made bump adjustable by using another brand canister. Nitrogen gas pressure can also be varied to effectively change springing rates.

Struts are Re-tubed to take larger capacity 175mm travel inserts. Long travel rally springs fitted onto adjustable platforms. 

BILSTEIN

910 BLUEBIRD RALLY SUSPENSION Struts 

Rear shocks and springs $ (ring for pricing)

BILSTEIN

510  Datsun 1600 race struts

With Serious adjustable camber tops 

BILSTEIN Sunny race struts

With Serious brake conversion 

SERIOUS®  STREET, RALLY, & RACE STRUTS AND SHOCKS 

FOR WHEN THE GOING GETS SERIOUS®!

Note! SERIOUS® is a registered trademark of Datrats.   Serious products are high quality components for Datsun/Nissan vehicles. 

NEW!  SERIOUS® STRUTS NOW AVAILABLE WITH EXTERNALLY ADJUSTABLE KONI INSERTS.

 Typical Serious® strut shock dyno chart

SERIOUS®   S/S KITS INCLUDE : - 

• Shortened strut legs to suit your vehicle, with special valve rate  shock absorbers.

• Adjustable height spring platforms, with race rated springs matched to the shock rates.

• Each strut and insert is stamped with unique identification number

• Strut is powder coated in your choice from a range of basic colours.

For Serious Suspension shocks and struts we don't just get an of the shelf unit and say that is what your car needs! We look at each vehicle as a seperate case and calculate the spring rates and shock/strut valve rates required. The calculations we make are typically based on the items shown below for strut based suspensions.  This helps give us a sound and consistent scientific basis for selection of components. Selection criteria include :-

1. The corner weight of the vehicle

2. Available bump (compression) and droop (extension) with the wheel/tyre combination you are using.

3. Intended use of the vehicle

4. Ride height required

Examples of how we would determine what your vehicle requires is shown in the column to the right.

To get the required spring rate in lbs/inch

Take the corner weight of the vehicle in pounds using a good corner scale .Support the vehicle body on stands. Remove the suspension springs and refit the struts and shocks. Set the vehicle to the desired ride height on stands and use chocks to set the desired ride height.

Raise the vehicle until the suspension is at at full droop. Measure the wheel travel from the desired ride  position. This is the droop figure at the wheel.

Lower the vehicle fully until no more wheel travel is possible, or till the wheel/tyre is a safe distance from contact with any obstructions. Measure wheel travel from the desired ride  position. This is the amount of available bump at the wheel. 

The spring rates required for the vehicle will be able to absorb most operating conditions without reaching a situation where the tyre will come in contact with the body or other components before the bump stops in shock are reached. To calculate the spring rate needed, we take the corner weight in pounds and multiply this figure by the maximum G force the vehicle will experience in normal operation. Simplified example calcs are shown beside. These will give a good starting point for spring rates, but may need to be varied depending on driving style and personal preferences. 

Valving rates

After the spring rates have been calculated, valve rates for the shocks are determined to keep the shocks within the designed velocity range for the valve system. This should occur without cavitation, or overheating of the damping fluid.

In extreme conditions, the fluid can carbonise due to the extreme temperatures reached during compression and subsequent passage through the valve system. Depending on the severity of the application, shock oil should be replaced on a regular basis.

Performance drops off and wear increases rapidly with carbonised fluid. Larger diameter shocks contain more damping fluid so are less prone to overheating and have extended service intervals.

Competition shocks should be checked oiled and re-gassed (depending on application) once every season.

Rally car example - A rally car with 550 lbs corner weight experiencing a typical maximum vertical G force of 3 G's with 9" of available bump would require 550 lb * 3G = 1650 lbs spring load  available at the wheel at this typical maximum load. With  9" travel available this means you have to support the full 1650 lb load over 9". The spring rate required to do this is 1650lb/9' = 183.33 lbs/inch at the wheel.

The actual spring rate required on the strut is determined by measuring the distance from the lower arm pivot to the centre of the ball joint and also the arm pivot to the tyre centre. Divide the pivot to tyre centre distance, by the pivot to ball joint distance and this figure will give the motion ratio of the control arm to tyre.

Multiply this figure (typically 1.1 approx) by the spring rate at the wheel (183.333 lb/inch and you get  183.33 * 1.1 = 201.63 lb/inch springs on the strut. There will have to be some compromise on rates determined by the available spring rates and lengths so opt for the closest rate. In this case probably 200 lb/inch springs. The spring length required has to exceed the wheel travel distance of combined bump and droop at the wheel divided by the motion ratio.  EG if the above vehicle has 1" droop as well as 9" bump travel, the the spring needs to be 10"/1.1=9.01" plus an inch or two at the fully compressed length before coil bind.

Street club race example - A circuit/street vehicle with 550 lbs corner weight experiencing a typical maximum vertical G force of 2.5 G's with 4" of available bump would require 550 lb * 2.5G = 1375lbs spring load  available at the wheel at this typical maximum load. With  4" travel available this means you have to support the full 1375 load over a 4" travel. The spring rate required to do this is 1375/4 = 343.5 lbs/inch at the wheel.

The actual spring rate required on the strut is determined by measuring the distance from the lower arm pivot to the centre of the ball joint and also the arm pivot to the tyre centre. Divide the pivot to tyre centre distance, by the pivot to ball joint distance and this figure will give the motion ratio of the control arm to tyre.

Multiply this figure (typically 1.1 approx) by the spring rate at the wheel (343.5 lb/inch and you get  343.5 * 1.1 = 377.85 lb/inch springs on the strut. There will have to be some compromise on rates determined by the available spring rates and lengths so opt for the next highest rate usually. In this case probably 380 or 400 lb/inch springs.