I agree about the overheating with the shark fin inner wings.
They may probably be fine with a standard 1275 cc engine, but as soon as you up rate the power (and as a consequence create more heat) you will get overheating issues without some form of cooling compensation elsewhere (e.g. ducting). It was certainly an issue for me. Basically you are boxing in all the heat in the small engine bay. Good for under trays aerodynamics....bad for engine.
This proof is born out by the fact that the later Mk3's had to have 2 extra chimney vents in their bonnets above the exhaust manifold to try and counter this problem....probably as a result of having the 1380cc (Avonbar?) engines as a factory option.
Midas Cars Forum Founder & Midas Facebook Group Page Founder (personal facebook account deactivated)
There are 2 solutions for this. First is to get air via hoses to the engine bay as I did with my turbo engine. I cut an extra hole in the bumper. This cured the overheating engine bay (but in a traffic jam it still caused problems). The second solution is to remove the rear edge of the bonnet. This creates a slot between the bonnet and the windscreen sucking out all heat. I found it on my first burgundy MK3 coupe which is now in Swedish hands. That car had the side panels, undertrays and an 1400cc Avonbar engine and never caused an overheating problem.
Any photos of these side panels, never once heard of them!
On a side note; I am thinking of adding another section to the photo gallery, for misc photos of midas' related things, such as an 'undertrays' section, 'exhausts', 'wheels' things like this, any thoughts?