For all things Rover V8, the TVR Griffith and Chimaera and TVR T-Cars

Let’s establish what terms we will be using so we know what we are talking about. Dampers do just that: dampen. They do not absorb shock. That is the function of springs. You can argue for other names but these are the ones that will be used in this article.

What can confuse is that TVRs use what are known as coil-over dampers, the name denoting the suspension springs are mounted around the damper. So the coil-overs provide two vital functions: springing and dampening.

In such an arrangement there are two main variables: damping rate and spring rate. Most coil-overs are fixed in the sense that the damper rate and spring rate are set when manufactured and that there is no simple way of changing either. As such they are, of necessity, a compromise.

As with any compromise, the setting does not suit all situations. Indeed they not only fail to suit some of the people all of the time but also do not manage to suit all of the people some of the time.

We will concentrate on the damping function leaving springs for a later article.

Function

The dampers’ role is simple enough. It absorbs unwanted spring motion. If there was no damper any force on the spring would cause it to vibrate – compress and extend – uncontrollably until the energy is transferred into heat in the springs. This would, for various reasons, severely restrict the amount of friction, or contact, the relevant tyre had with the road.

I have had a front damper fail and it was most obvious when braking as the tyre was lifted from the ground, then locked, then was pressed back onto the road making the wheel rotate and then cycle repeated

itself. Whilst it was, to say the least, exciting, I never felt the urge to repeat the experience.

A damper, reduced to its basics, could be described as an oil pump. As the suspension is compressed or extended so is the damper. The damper exerts pressure on the hydraulic fluid it contains so generating heat. As a fluid cannot be compressed (accurate enough for this explanation) it has to go somewhere and that is through orifices in the piston. The larger or more numerous these orifices the less heat is generated.

So the energy in the spring is converted into heat so slowing the movement.

The oil is forced through the orifices in both the compression and extension cycle (2-way). There will normally be more resistance, i.e. more heat given off, in the extension cycle.

That alone would be clever enough but dampers are also velocity sensitive: the more energy in the initial compression or extension the more resistance provided by the damper.

Just to make things interesting, the damper is subjected to two main types of force: those generated by cornering or braking and those when you hit a bump or pothole. Both are complex but with the pothole, first there is the extension as the ground falls away and next there is the often violent compression when the far side suddenly pushes the wheel up. Remember that the relevant side of the car would have started to go downwards thereby increasing the load.

There is an argument that the forces generated in cornering are the most important concern with high-powered sports cars. The better the dampers are at coping with these forces the better the road-holding.

Upgrades

The standard dampers as fitted to TVRs are perfectly adequate. However, their limitations must be accepted. As stated earlier, they are, of necessity, a compromise although that doesn’t mean they are wimpish. In any back-to-back comparison with a saloon car, even a sporty one, the difference in a TVR’s setup will be obvious. If the standard dampers are perfect for you then there is no need for you to change.

But for those who require a bit of an upgrade, a substantial change or something that will suit both road and track-days then adjustable dampers give great improvement for a very reasonable charge.

Racing Green Cars of Hampshire has just started to market its own bespoke dampers, produced by AST, suitable for all TVRs, from Griffith to Sagaris. But that raises the question as to why they didn’t go for one off the shelf. There is, after all, quite a range in price and quality. Colin Bowdler, of Racing Green Car, said:

“We wanted something specific to TVRs. A damper that would have a limited range of essential settings rather than dozens and dozens, the vast majority of which people would never use. We also wanted to establish a dependable quality level so that people could buy them with confidence. There can be no argument that AST are amongst the leaders in their field.

“We looked at Nitrons, were impressed, but decided we wanted something a bit better but at a competitive price. It has taken time but AST have worked miracles and come up with dampers that we are very happy with.

“We opted for twelve settings, all of which are useable. There is a small but significant difference between each setting. We’ve tested dampers where you could turn the adjuster three or four clicks with no noticeable difference. All these adjustments might look good on paper but practically they are a hindrance. There is no point to them.”

Racing Green Cars paid particular attention to the bushes, opting for a high quality one from BMW.

“The life expectancy is in excess of 150,000 miles. We wanted quality all the way through. And I believe that’s what we can offer.”

A development set had been fitted to a Chimaera and I was given a ride in it, driven by Woody. He was obviously very pleased with the dampers and threw the car around, drove over poorly surfaced roads and picked out rumble strips at the side of the road to show how well the new dampers coped with all the problems of modern roads. Which are, of course, likely to get worse.

Most noticeable was the way the car coped with potholes. You felt them, of course, but they didn’t

seem to upset the car to anything like the extent they would have done to a standard TVR, even one that was new.

The dampers were set to what Racing Green Cars felt would be a good median. I have to say that the ride was excellent with, as you would expect, firm damping. The setting allowed the car to remain stable on corners without subjecting the occupants to any pounding on bumps.

Woody suggested that if someone drove regularly on such roads then a softer setting might be worth a try. After all it would be easy enough to experiment. All you would need to do is turn the dial on the top of the damper a click or two and then go for a drive. The thing is that ride resilience is a very personal thing. There are no rules apart from doing what you want.

These new, TVR specific dampers are available now. Contact Racing Green Cars to discuss your needs and for prices.

As mentioned in the text, springs can be adjusted. The allen keyed bolt is unscrewed and the bottom ring rotated, extending or compressing the spring.
Sprint rates will be covered later on RV8R.

Thanks to Racing Green cars of Hampshire for their help in compiling this article. Click on the picture, right, to be taken to their website.

Racing Green Cars
Station Road West
Ash Vale
Hampshire
GU12 5QD

Telephone:
+44 (0) 1252 894840
Facsimile:
+44 (0) 1252 894789
E-mail: colinb@racinggreentvr.com