14-10-2019, 11:05 PM
Spurred by the fact that second hand kits fetched almost the price I paid, and assurances from the PM that would always be cheaper than petrol, I labouriously converted my Jowett to CNG. Made venturis of wood to facilitate experiment and these proved far less fickle than the low obstruction mixers fitted to more modern cars. First the propane was stripped from CNG further reducing its punch then the whole programme faded as latest cars with electronic controls became less suited. Tales abounded of melted carb components, floats rubbed through, perished petrol lines causing fires, endless expensive tune ups, hard starting, grossly pocketed valves etc. Cars with auto adjusters would reach the stage where barely go! But in the Javelin it did solve carb icing and with 1cwt in boot it rode well. Oddly valve recession was less than on petrol. The kits became worthless and after several years use I possibly broke even! It was interesting to calculate the loads on the cylinder about 18 inches in dia!! I dont think any exploded in crashes but one or two during filling. I still have half full of gas. It was remarkable that the mixer fed at 2,000 psi or so could respond to variations in suction far less than in a carb venturi.
Nothing to do with Sevens except that I wish I had spent the considerable effort on the Seven instead!
Nothing to do with Sevens except that I wish I had spent the considerable effort on the Seven instead!