06-03-2019, 12:32 AM (This post was last modified: 06-03-2019, 12:34 AM by Bob Culver.)
Without an oxygen sensor, to get settings optimised for performance and economy can be protracted, although simplified with a low power car. Whilst carbs can often be transferred between similar engines with little alteration, twin carb settings for a 4 are markedly more weak than for same carb used singley. With a balance pipe single carb venturi usually too large. I presume jets and any air bleed tubes are cheaply available.
With twin carbs air leak problems are increased and slow running often challenging. Tuning difficulty increases at least as the square of no of carbs!
If anyone has ever played with twin 26VA may be helpful.
Many cars have thick fibre gskets to reduce heat, but will bonnet clear?
I would have thought the advantage of twin carbs would be negated by using the standard cast iron exhaust manifold? I have seen a period photo of a GE Brooklands with two 30mm updraft Zeniths which seems like overkill. There are a lot of fast cars running on single updraft carbs in VSCC events, I think that understanding of Solex’s has improved in recent years with people like Robert now able to service them and provide the right bits.
I have written an article on these two companies which is due to appear in the spring and summer VSCC bulletins.
Although the Twin Solexs look great, particularly the barrel type. I had a terrible time trying to tune them with my air fuel ratio gauge ended giving up and went with a single. An SU gives you much more control of the mixture, a poor man's fuel injection.
Never having strayed from the true path (other than a brief affair with a PA MG where I found SU's) I hadn't seen the side draught Zenith although they are featured in the small 1924 Zenith Carburetter booklet .
I wonder why early Austin Sevens weren't fitted with these ?
