Let me preface my response by saying I am not an expert on SCCA racing, but I recall reading many years ago that at some point SCCA began requiring a return spring on each carb, obviously for safety in case of linkage failure during a race. Possibly other race sponsors followed suit. It is possible your car was set up that way for that reason.
Here is the response that MG came up with, rotary springs on each shaft. At least they would not add to the shaft wear.
1 Like