iv just fitted a new -31 actuator on my s2, the boost gauage peaks at 12 then holds 10 and drops down to 8psi.flat out in third. have i got a boost leak or is this normal. should i have the boost set higher,im useing standard intercooler,the ecu has been chiped.when i brought the car the guy said it wos running 12psi boost, should i set it 2 peak bout 15 then hold 12. I live on the isle of wight so have no exsess to a rolling road with out traveling to mainland.any help would be appreciated.