1972 Hillman Imp "FAF"- Pedal Box

Right,

So as you've already seen back on page 1, the car went to Carl for some god damn sexy front shock mounts. They are about 12cm higher than standard, which for the same length spring/shock lowers the car by about the same amount.

However, that's not the end of the front end mods.
One of the problems with rapidly altering the altitude at the front of an imp, is that you lower the pivot points of the front suspension arms. With substantial lowering, this means that your arms are angle upwards towards the outside of the car as the pivot ends up much lower (in the centre of the car) than where the stub axle mounts to the wheel at the outside of the car.

The "undesireable" aspect of this, is that you suspension starts to move in and out, instead of up and down.
The arm moves on a circular arc about the pivot point in the middle of the car. At the outter quandrant point of a circle, the movement is mostly up and down, where as if you go up past that, the movement starts becoming side to side.

In order to ensure the wheel moves up and down instead of side to side, I decided to have the suspension mount points raised. In doing so, I have ensured that the suspension arm is close to parallel with the road at ride height (where as before it was angled up towards the sky).

This happened in two phases. The first phases was to have the whole of the front floor/wheel well section removed and then raised about 75mm.
The imp steering rack bolts to a plate, which also provides the mounting point for the rearmost suspension arm mount. Obviously, it's important to ensure that the suspension arm and steering rack are moved by the same amount, otherwise I would end up with a bunch of bump steer.

Luckily, as ever I had to top guy on the job in Carl:

<Can't find any photos! They must have gone AWOL when I changed phones a while ago>

Unfortunately, this wasn't a perfect solution, because the original chassis rails were proving a bit of an obstruction and restricting suspension movement.
Back to Carl the car went, who fabricated new chassis rails, installed them and then removed the old ones. At the same time he also removed the spare wheel well, making the steering rack and suspension mounts much easier to access. As a result, there is tons of room for the suspension arms and track rods. The only obstruction now is the top of the inner wheel arch.

So the finished article looks like:






It looks fantastic and to the untrained eye, looks like a "standard" front end of an imp!
And that means that this can happen:






(Video)


Ultimately, at the moment I have about as much suspension travel at the front as a completely standard imp and if I wanted to could run standard imp springs!





For the really techy ones amongst you... raising the front suspension will have reduced the roll couple quite alot-
Lowering the car will have lowered the front CoG- reducing the distance between roll centre and CoG, resulting in a reducing roll couple.
Raising the front suspension has raised the front Roll Centre, reducing the distance to the CoG and the roll couple further.
This in turn is likely to mean less roll at the front. As a result I've picked a slightly softer spring for the front end, but will be creating as detailed a simulation of the vehicle dynamics set up as possible.
Also to consider is the roll axis- which is the overall axis between front and rear Roll Centres. With the front higher than the rear, you can expect the car to understeer, with the front lower than the rear, you can expect the car to oversteer.