Stock boost gauge

[raceguy]

What is the stock boost gauge supposed to read under full acceleration? Mine seems to only read about 5-6 psi. Would a dirty air filter cause a serious loss in boost? What would be some other causes of lesser performance in a 194K mile DSM?

 

[GSX90]

Your stock needle should be going higher. You might want to check for any boost leaks as well as your turbo. With the car off, take off your turbo inlet hose and see if the turbo blades spin freely by hand. Checking your air filter is also a good idea...hope this helps.....