Suspension
The cars > Developments and changes
Ok....
Two things happened towards the end of the 2014 season that lead to some significant work being done on the car over the following winter.
- The Engine "Blew up"!
- The curent suspention was not woking as well as it might.
Suspension observations;
- During the last couple of events (especially at the Bovington event) it became increasingly apparent that the suspension on the car needed some attention;
- It would bottom out heavily, or
- It would catapult the back end into the air, sometimes with terrifying results.
- The suspension that was on the car was very good and had done very good service. I have no real complaints with it, as most of the time it has been very capable on the cat1 and more level "tracks", however, on really fast rough or undulating surfaces the lack of travel was becoming evident.
The suspension rebuild.
After talking to various people about the suspension behavior and discussing the best way to overcome the issues with things like hydraulic bump stops and/or new dampers etc. The one recurring piece of advice became apparent and that was to upgrade the Varidamp shock absorbers. These have proven to be very good shock absorbers, however the conditions we are using the car in require something a little more.... Aggressive.
From; the current Millner Varidamps (with the standard 8" of travel)To; 2.5" remote Fox's (with 12" of travel).
Again I must reiterate that the Varidamps are very good and simple to fit as they use the stock mountings. The Varidamps make a good cost effective upgrade to any land rover style suspension, however, the travel limitations and the mounting methods constrain just how much they can do on really fast & rough surfaces.
The Fox shock absorbers have subsequently proven themselves to be very effective and made a substantial change to the handling characteristics of the car and in doing so improved the overall performance of the car.
So
this is what we started with, and how we had set up the Varidamp shock
absorbers using an off the shelf after market shock absorber turret, I
must say looking back at this it all fits under the wings very nicely.
At this point the damper reservoirs were mounted inside the engine compartment on the front.
SO; after much deliberation the checkbook was found and these where the result, and yes that's a 12" rule for scale these new sock absorbers are huge and definitely do not fit the standard land rover mountings. Getting these under the bonnet was going to be a challenge as one of the main aims was not to disrupt the profile of the car.
A little bit of a comparison between;
- The new Fox, (on the left).
- A standard Land Rover fitment (Centre).
- The Varidamps that where removed (on the right).
Tornado Motor sport provided the frames and brackets to be able to relocate and mount the new shock absorbers, as the intention was to mount the rear shocks in a vertical format and the new larger shocks need a different mounting solution.
With the engine out of the way to be replaced with a rebuilt unit and now having all the new components, the installation of the new shock absorbers could be started.
There where several parts to this mini project.
There where several parts to this mini project.
- Modifying the front and rear axels to accept the new rose joint type of attachment on the end of the new shock absorbers.
- Fitting the new hoops for the front shock absorbers in sutch a way to accommodate the additional height without upsetting the external profile of the car.
- Fitting the new hoops to the rear of the chassis so that the rear shock absorbers pass up through the middle of the springs.
- And as as the front axle was removed for the mod's as a part of this job we took the opportunity to fit a new front diff pan, larger and stronger so that a front diff guard is no longer required.
The front hoops are welded to the chassis using some reinforcing plates and bolted through the steering bolt holes for good measure. These are not going to move if we have anything to do with it.
Front hoop fitted and additional struts fitted to stop any movement or flex.
The spring seats on the front axel have been cut and modified to accept the bottom rose joint to maximize the available shock length whist keeping everything under the bonnet.
A new bracket has been built within the spring seats and the bottom spring plates have been welded in place.
A new bracket has been built within the spring seats and the bottom spring plates have been welded in place.
The Pictures shows everything in place and give some impression of just how much difference 4" makes in terms of the additional "drop" on the axel, this is still being constrained by the bushes on the radius arms etc.
Note the reservoirs located on the front of the hoop as we where unable to find any space inside the engine bay now, These later get moved to be on the hoops under the front wings. There are new inner-wings to accommodate the new shock absorbers and hoops.
Note the reservoirs located on the front of the hoop as we where unable to find any space inside the engine bay now, These later get moved to be on the hoops under the front wings. There are new inner-wings to accommodate the new shock absorbers and hoops.
A similar arrangement was used on the rear shockabsorbers however fitting the hoops etc. was comparatively easy as there was a lot less concern about keeping it all within the body panels. A new fuel tank can be seen in the background As the previous tank split (the advise here is fit a tank with straps not "tab" or "Brackect" fitted directly to the tank).
And Fianly the new Diff pan in place (and painted).
One photo was taken with the axle jacked up against the chassis with bump stops removed to test and check that contact with the engine is avoided! It's very close, however, we are working on the principle that if things do get this close in normal running conditions we probably have a bigger problem to deal with?
One photo was taken with the axle jacked up against the chassis with bump stops removed to test and check that contact with the engine is avoided! It's very close, however, we are working on the principle that if things do get this close in normal running conditions we probably have a bigger problem to deal with?
Postscript.
During the Radnor event 2017, We had issues with the rear suspension binding up. We where not the only car to suffer this due to the nature of the course set out. Subsequently we learnt that this is not an unknown problem with these shock absorbers, however it is easily rectified with a set of uprated piston seals and a service!