it\'s a knock off replica of a tial wastegate, still does the job. I\'d say it\'s running the correct spring.
If cars been tuned to run at 20psi peak, a mbc set @ 15psi will do the job, but you will prob find will make the car run a bit poo rather than running as if the boost has just been turned down,..
its going over 20 psi, boost gauge goes till 20 psi, however when we r on full boost, it goes way more than 20, i would say 23 psi at least, so, if he buy a spring for 15 psi for tial wastegate should be fine ay ?