Over the last month, (inspired by Primabaleron’s amazing work), I have completed the entire rear end of the C9 (with the sole exception of the rear wing supports which I will add at the last moment as they look very flimsy)!
The engine was relatively straightforward. I was concerned that the joint between engine and firewall was so fragile (2 small screws to the back of the cockpit) and so I was careful to ensure that the plenum chamber connected decisively to the intercooler pipes to give the top of the engine some real strength. I kept the floor of the car attached to the cockpit section to keep the overall assembly as strong as possible whilst I worked on all the wires and pipes around the engine – a process that lasted many days. The floor also acted as a very good reference plain to enable me to set the exhausts to the correct height for the turbo assemblies on each side which are attached much later. (I mention this just because the instructions indicate that you should work on this section without the floor being attached.)
The Ocean Grey frame that carries the rear shock absorbers is the key to the strength and the alignment of the whole rear of the car. You can only attach these by detaching the floor and manoeuvring them around the exhausts before clamping them to the rollover frame. As they dry, you can attach the polished metal crossframe (and anti-roll bar) using two micro-screws that are inserted under the shock absorbers which also ensures they are exactly in line as the epoxy glue dries. You can then re-attach the floor.
Moving onto the gearbox assembly, I chose not to fix the oil radiator and the prominent rear bodywork support frame until I could be sure that the frame would exactly fit the receiving holes on either side of the rear floor. I found that the various PE parts fitted well enough and it was just a case of ensuring that all the holes were properly opened up for the suspension and oil pipes. I found I was able to attach the gearbox precisely over the single screw hole in the floor that ensures it is perfectly aligned when mated to the engine and I then built up and attached the suspension on either side (leaving out the rear lower wishbones). I struggled with the rearmost gear linkage shaft which I needed to extend by about 2mm to fit snugly at front and back.
After completing the whole gearbox and rear suspension, I carefully removed the floor for the last time to paint it and build up the various PE parts that fit into it behind and below the exhausts. Then came the moment of truth when I presented the entire cockpit, engine, gearbox and suspension/uprights to the floor and committed to using glue! The tolerance around the exhausts and the PE shields that box in the exhausts was almost non-existent and I needed to use a small screwdriver to prod and push the PE parts so they fitted perfectly on either side of the car. I was really relieved that nothing broke at this stage and as the whole assembly dried, I attached the rear oil radiator and the metal bodywork support frame which fitted (with a tiny bit of persuasion!) into the floor on either side.
There was one hiccup after this stage – namely the lower rear wishbones. You are required to enlarge the holes in the floor through which these pass on either side but even having done this, I found there was no way to wiggle them to sit precisely below onto the uprights and at the same time get the locating pins on each arm to fit into the pre-drilled holes on either side of the gearbox. In the end, I had to bend both of them inwards significantly to get them to fit through the holes and then re-bend them outwards before attaching the inboard ends. You cannot actually force them into their location holes – or at least I could find a way to do so. I think a better option would have been to cut away the rear central section of the floor itself to expose the whole gearbox underside - and then re-attach the floor once the wishbones had been attached.
Finally in this section was the dreaded turbo assembles which I always hate. The 3d printed exhausts are lovely and light and fitted easily. However the turbos themselves were difficult to position perfectly as there is very little room in which to work due to the vertical PE plates attached to the floor behind each one. I actually drilled a hole through the turbos and inserted a horizontal metal rod which allowed a much more positive join with the air inlets and turbo exhausts. I think I will always do this in future! The upper PE plates exactly fitted around each wastegate mounting point and I weathered these with Alclad colours before attaching the wastegates themselves. I overdid the smoke on the yellow Kevlar intakes on each side in front of the turbos and so I added an extra layer of decals here. When the bodywork is attached, you will not be able to see the front of these intakes and so I did not waste further time on them.
I hope these photos are of interest to anyone else who attempts this project. If you do so, please consider using the floor as a base to the model throughout and attaching the cross frame to the back of the engine to close up the reinforcing frame rather than attaching it to the gearbox and attempting to attach it to the engine later. I would also suggest cutting out the rearmost centre section of the floor to allow easier fitment of the lower wishbones and then adding it back afterwards. I think these were probably my most useful “learnings”!
I reckon I am now about 2/3rds of the way through the project and so I am hoping to complete the model by early November. However a two week holiday to Turkey might get in the way of this aspiration. However it will be nice to have a break before contemplating those doors...
Best regards
Hugo
PS I am sorry that the photos are in reverse order. I couldnt work out how to turn them around!!
