Originally Posted by Lorry

Why not just get a 1 bar spring and then run either ECU based boost control or an EBC to make it run up to the target of 1.4 bar? If you put 1.5 bar worth of spring into the wastegate then it can never run lower than 1.5 bar unless you change the spring again. Unless there is a good reason not to have it electronically controlled this is what I'd be looking at doing.