September 2003

This particular car / case is not straight forward. It is a very old model (1980-1984) hence it is not main stream anymore. There is no design / specification for this car.

Due to this, TiTAN (we MPD Auto Centre Sdn Bhd) will need to "Engineer" the suspension from zero.

The task was quite daunting to think about in the beginning, especially when this customer asked for "Rear Coilovers" which was technically not necessary.

However seeing how pitiful this customer has been with his quest for proper suspension solution, we decided to take up this very difficult challenge and help this guy once and for all. You may see how this customer has suffered through ill-advised purchases and matching of previous suspension setup - customer's misery

Before starting work, the car's current suspension system was looked into. The resting and lifted stroke was measured.

The coil's spring rate will be decided later, once the old suspension is taken out and placed on a hydraulic press to measure it's basic capability eg: xx psi / 3 inches.

During the investigation of this vehicle, the following issues were noted: -

Front resting to listed stroke was found to be 75mm which is very good, however upon closer inspection the travel was "NEARLY" all "HELPER SPRING" they are not from the main coil itself. This means this the absorber's movement is "NEARLY" completely un-governed by the main coil. It is purely on the absorber's up-ward stroke alone. This oppose the law of physics and it is no wonder why the customer is complaining about true handling, stability and controllability. There was simply no control.

Saying this, why the stroke was fully "HELPER SPRING", because the main coil was found to be around 8 kg/mm and the car's front weight was not enough to "LOAD" it. Only a mere 15 mm or so was displaced on the main coil due to the car's weight and this indicate that the coil's spring rate is simply too high.

It is difficulty to judge this since the absorber's re-bound was found to be very very strong.

Rear resting to lifted stroke was only 5 mm. This is ridiculous, it is no wonder why the customer complained that he was unable to put his foot to the accelerator to the metal. The car is bouncing too much.

The rear coil was found to be around 6.5 kg/mm - which again was too much for such a light weight rear end.

The existing suspension system's basic physical dimensions were written down, knowing it's current stroke, and estimating the OEM's stroke and spring rate. The work begins..............

This customer had a spare front strut casing, hence we worked on it before needing the car, based on findings above.

The customer's OEM unmodified strut casing

The old strut casing is machined away and the new TiTAN's tube goes in and welded on the bottom on the knuckle.

The angle of the strut casing was preserved

It is then spray painted - powder coating finish

When this was complete the customer was requested over and asked to leave the car for at least two days for complete installation. Normally it only takes half a day for main stream models, but when working on a completely zero design, we normally need two days if all goes smooth.

During the installation of the front, we encounter a un-foreseen problem. The "STEERING ARMS" ball joint is blocking the knuckle and could not be installed.

Since the customer previously mentioned his interest to using a "Roll Center Adjuster" hence a pair was made for him - FOC.

With this the front installation is complete with the matching of a approximate 5.5 kg/mm spring. The total effective stroke is 150 mm, which is equivalent is TRD's standard of main stream short stroke.

The resting to lifting stroke is 60 mm, which means it's got plenty more for downward stroke (around 90 mm left) and that this particular 5.5 kg/mm coil is 330 mm means the complete front movement will be 100% 100% 100% within the very linear range.

The absorber's valve position is particularly positioned and manufactured to match the resting position for optimum valving behavior.

The rear was solved by traditional method of maintain the coil to coil replacement and absorber remaining to be telescopic and not coilover as requested. Too little space - very dangerous.

A typical coil was used. However the customer was not satisfied with it saying there was too much a difference between the rear and front. This was completely expected so the rear coil was further cut to increase the spring rate from around 100 psi / 3 inches to 200 psi / 3 inches.

Due to the lost of several round of coil, the rear height has dropped significantly and a custom spacer was immediately machined to regain the lost height. Again this is FOC. It's all under the TiTAN solution package. Here we strive to be the best solution provider.

With this the customer express extreme satisfaction :)

However the customer still thinks that the rear is too soft compared to the front - as expected since we have not got the time to re-valve and re-pressure and re-set the absorber to match the new spring rate. So the rear telescopic absorber was removed and re-set accordingly.

This time the customer was again amazed at our quick response and no nonsense excuses solution. He was very very pleased and told many of his friends and introduced our product to allot of people.

We are pleased to have served this customer and solved his passion for handling and control.

However two months later he returned and requested to increase the rear spring rate even more. Saying that the rear 200 psi / 3 inches doesn't match the front 500 psi / 3 inches very well. He keep insisting to have rear coilover.

This customer insisted to use the 300 psi / 3 inches for the rear, which would be a closer match to the front knowing this vehicle's front rear weight distribution estimated around 55% 45% after installing new engine.

After several nagging from this customer, we finally gave it very very serious look into making the rear very very tight space to fit coilovers. Originally we were going to install a coil-height-adjustable-mounting on top of the existing. However this was even more "small".

So, the search for a small coil diameter having around 300 psi / 3 inches and travel of around 300 mm begins. This customer was very lucky. The coil manufacturer was brought in some prototypes and were possible to fit.

There was significant concern of using the coilover to put all the stress onto one point on the rear axle. However the customer was very sure and insist to take full responsibility and not blame us. We just couldn't refuse and let down such a customer, so we did it. Since the customer mention people all over the world has done it without problems.

So, the new rear coilover is born: -

Since the work / modification is based on the existing telescopic absorber, hence the usual coilover spring seat gears cannot be mounted. The spring loaded lock step type method is adopted.

Finally the rear coilover is installed. It is up-side-down. The only one of it's kind. We don't think there would be another set like this :) - we are proud to be able to do this.

Our inverted twin tube is not double inverted :)

The story is not over for this guy. After approximately 6 months from day 1 of installation. He returns request to reduce the front spring rate from 500 psi / 3 inches down to 400 psi / 3 inches. Saying it understeer allot. This was only found out after he participated in the local "Street Shoot Out" competition.

We were glad to comply to his request, since we would like to know what's the response of the car would be. This particular customer put allot of thought and attention to the overall handling of the vehicle.

Quote from the famous Bill Sherwood after changing the front coil from 500 psi / 3 inches to 400 psi / 3 inches. This was a regular drive without letting him know of the changes. It was only 10 minutes after the drive and into the 3rd corner.

"Chin, what did you do to the car? it seems to be turning much better than before!"

So, looks like this customer hit the bull's-eye on this change.

Please see the customer's own website for his version of testimony

http://www.my-acoustic.com/Car/TITAN/titan.htm