This is an interesting discussion.
A rear facing scoop with opening as close to the windscreen is good; here is a high pressure zone - 100% true. As you all say. After looking at all kinds of pressure zone/ IR- photos of wind tunnel cars I could come across- the highest pressure zone is to be found at the front of the car- at least on a road car with some frontal area. (On a sleek can- am racer the picture is different.) That is why I scooped the air fron the grille, which ofcours also serves the rad and the
oil cooler. And also- of course- hot & unwanted under-bonnet air is going out on the middle flanges of the hood- a low pressure area.
As a friend did the wool- thread/ yarn- test, I do not trust him and will do it all over again to see what conlcusions i can find.
Yes, Jac Mac- you are probably correct on the "too much air under the bonnet" theory. In the pictured Capri there's much more restricted front air intake area than on my friends ride. Hopefully, it will do wonders... Also a different outcome of the Wooly experiment.
Very interesting to see you have been working on the NZ Capri racers. Been looking at some V8 Capri's from the green island, although some time ago. I have read alot of your posts in the Weber- department. I was 100% certain you inhibited US of A as Capri's are quite popular as a racer there, as well. (Although- used to be is a better statement- there were more in the 80's, as I understand, than now.)
It's a small world and you come by people with Euro- Capri experience wherever you go. Her, there, Corner Carvers, SBFtech and Club Cobra.