max-it-out wrote: ↑Fri Dec 13, 2019 9:20 am
So you seem to be saying that all the Stromberg CD s as fitted to US spec cars can be adjusted.
No, not really on S2s they can't be adjusted very much. The Jaguar Service manual in the Emissions Section gives an explanation on what can be done but basically unlike SU's each carb was individually calibrated during the production process so that it's performance would be identical to that needed for efficient operation. That way it would continue to function at the right settings without anyone being able to get in and "improve" it.
Eventually it would wear out and there were some components you could service along the way - as described in the Jaguar Service manual - but Jaguar went down this route of using a more expensive carburettor than an SU so it would always give as near as possible correct mixture without the tinkering and adjusting folks do to SUs.
Confusion arises because there were versions of Strombergs which externally look very similar which did have an adjustable jet and were used on other cars at the time. If you want to fiddle then arguably you could fit a pair of those but at that point you could also fit fuel injection, triple SUs, even twin SUs as Jaguar used on most XK engines. The choice goes on.
On my car the front Stromberg already had the tapped vacuum take off point for the distributor vacuum advance in the carb body but just not drilled through. I fitted an appropriate barbed brass adaptor, used it as a guide to drill out something like a 3mm hole into the carburettor body in the correct place above the throttle butterfly and it works perfectly. I didn't need to remove the carb from the car.
