I last had my car setup in Jan 2005 but have noticed the boost has been dropping off the last few months or so,used to run about 1.5 bar with not much pre load required on the actuator as the amal valve had been jetted by M.A.Dev at a previous visit, the boost has slowly dropped down & i have shortened the act rod to compensate each time which has worked but then over a period of time it looses a few psi & have to shorten rod & so on. its dropped to about 1 bar recently & the actuator is almost at full adjustment. Have checked the amal & that is ok as runs 0.5 bar when feed disconnected to amal valve, have had a quick check for leaks but can't see anything & their is a good vacuum reading on the boost gauge at idle, can the bailey piston dv leak ?
the actuator is about 3 yrs old , is it poss the springs gone weak ?

Any help appreciated.

Cheers Simon.