Michael,
I decided to use the Zeniths for a blend of reasons, some of them irrational I am sure!
I do like their look with the coopers. I sorta think the pancake air filters were for home use, with different filters for export, but what can I say. I like the way they look - and sound!
As for performance, I am told that on paper they do as well as the Strombergs. You be the judge as I am not in any way sufficiently knowledgeable to know. They are simple basic carbs with a good feed of fuel. I hope they are easy to adjust and to sync.
I hope in addition that the Zeniths can be modified should ever my fantasy of Stage II tuning come to fruition. I asked the carb guys if different throttle bodies can be obtained and the yes I received was tempered only by my lack of knowledge whether I'd do that, or just what. Time will tell!
I'll sure do a post when & if fuel weepage takes place. That's experience talking, which experience I don't yet have. I don't much care though, it just adds to my greater enjoyment to have another something to tune and tinker.
My former S IV was 100% stock. That was normal for Alpines a few years after Chrysler pulled the plug. It was a tired S IV though, and I blamed the Solex. My ignorance I am sure, but I felt I'd not do Solex again. I am sure I made a bad decision on that.
My former S V had Strombergs and they ran strong. They are great carbs. I debated switching to them as I have a pair and manifold with linkage, that only need some TLC, perhaps.
But the Zeniths/coopers are such classics, and offer no substantial performance penalty that I know of, that I just had to keep them for a go.
So...that's that for the Air-pine!
Rgds,
allan