A large section of the firewall and the transmission tunnel was removed and the engine and gearbox wrestled in to position. Whilst the final position still needs to be worked out, it does show roughly how it will sit and what room I have to work around it. From initial looks, the passenger side mount will be straight forward to fabricate but the drivers side will require a bit more work to get it strong without being too bulky.

The main bars running from the main cage front legs down to the front of the chassis rail have been fitted, this took a lot of effort and measuring to make sure that they are symmetrical as they will be holding up the suspension loads. This has allowed me to fit up the steering rack, suspension arms and hubs and bolt on some wheels to check how everything fits. There are some clearance issues that will need to be resolved, the big one is that the upper inner guard sections that hold the guards in place need to be much smaller, I was planning on keeping these in place to reduce the amount of work required but they will now be removed. The good part is this should reduce some weight out of the car.

As the remaining work in the front end requires the engine to be in place for clearance checks, the firewall has been cut to allow the engine and gearbox to sit in place. When they are placed in there, it might start looking like a car again!

Whilst there has been a lot of fiddly work to get to this next stage, I am keen to get it complete as it will mean that the car will be able to roll on it’s own suspension again. Something it has not been able to do for a couple of years.

Got a few things to do to make it a little better for the next event. Firstly, the LSD needs to be shimmed up and put in. It’s too hard to turn it in on the tighter corners, the long wheelbase and welded diff is not a good match. Secondly, it tramps like a bitch way too much. Got some idea’s on getting the shocks to work better and then put in better shocks to help some more. Thirdly, it got a little warm a couple of times and the oil light came on towards the end of the faster runs at the end of the day. Going to flush out the cooling system and add an oil cooler. Extra oil capacity can’t be a bad thing. Finally, and most importantly, it needs to be louder! I’ve been getting a lot of complaints that they couldn’t hear the car coming so we will have to do something about that!

With all of the parts in place the geometry was checked and it showed that there were massive amounts of bump steer (when the suspension compresses over a bump the wheel also turns in or out causing it to unsettle the car). On the factory setup, the outer tie rod end is inserted froim below the steering arm section of the hub and is angled so that the pivot of the tie rod is closer in to the wheel to give the correct ackerman angle. To reduce the bump steer, the steering arm has been rotated to point in a more appropriate angle for the tie rod to be inserted from the top. The tie rod will also be replaced with a rose joint and bolt setup to allow the outer pivot point of the steering to be adjusted for height which can be used to fine tune any bumpsteer.

Parts that still need to be worked out are the sway bar mounts and steering rack mounts to rotate it downwards so that it points to wards the steering rack better. Once that is complete and the sections welded up and braced, it can be transferred to the car.

The pictures below show the standard MX5 setup as well as the mockup new setup. All pictures are of the passenger side of the car.

An MX5 front cradle with hub, arms and steering rack was obtained and a lot of measurements taken. It was obvious from early on that the height of the front chassis rails was far from ideal for a low ride height and will need significant cutting to allow the lower pickup points to be in the correct location. The second more concerning problem was that the width of the lower arms put the rear most mount inside the cabin of the car. In order to get around this the arms will be swapped side to side so that the long section of the arm points forward and away from the cabin. This will require more work with ensuring the geometry is correct and that the steering rack does not make contact with the arms.

Work has started by placing a section of the cradle in the engine bay and cutting both the inner guards and chassis rails to double check that everything will fit and work as anticipated. Cutting the inner guards is not as problematic as it would first appear as the move away from a strut setup means that they will no longer be a significant part of the chassis. Upper mounts will need to be made for the new shock absorbers but they will most likely be included in the forward section of the roll cage when it is built.

Now to move on to one of the many other jobs.

Some of the more obvious parts are the adjustable tubular control arms and bilstein coilovers. The harder to spot bits are the 4.3:1 LSD, bigger brakes with slotted rotors and adjustable sway bar.

Most of the chassis work at the rear has been completed enabling the cradle to be fitted up shortly.

Excellent work and it fits exactly like it should. It still needs a bit of work on port matching and correct bolts/studs, but it does mean that the quads are bolted on to the engine now.

The only fitment issue I have noticed so far can be seen in the pic below, underneath the masking tape is a coolant passage that has a 10cm or so piece sticking out that no longer fits. I’ll have to get something fabbed up to route the coolant and mount the temperature sensor on. Not a big issue, just something to add to the to-do list.