Why Doesn't My Boost Gauge Show The Right PSI Reading?

On a standard car, you should see 5-6 PSI on your boost gauge at WOT (Wide Open Throttle) with a standard size pulley, and 9-10 PSI with a 3.4" or 10 PSI pulley.

Modifications such as Cams, High ratio rockers, and free-flowing exhaust systems which help the engine breathe better, can reduce the pressure build-up in your manifold as your engine is now able to consume the air faster. This is perfectly normal and can cause your boost gauge to show less pressure.

However, if you have some common mods such as an exhaust system and you still only see 2-3 PSI at WOT with a 10 PSI pulley, then unless your boost gauge is faulty you should consider disabling your boost solenoid as it is common to malfunction and cause a serious loss of boost pressure. Disabling the boost solenoid will not cause any undesired sideffects to your vehicle.

Please click on the links below to view some photos as a guidline when disabling the boost solenoid.

http://www.maceengineering.com.au/WebRoot/ecshared01/Shops/mace/MediaGallery/new_images_10-11-11/Boost_Solenoid_Disable_1.jpg

http://www.maceengineering.com.au/WebRoot/ecshared01/Shops/mace/MediaGallery/new_images_10-11-11/Boost_Solenoid_Disable_2.jpg

http://www.maceengineering.com.au/WebRoot/ecshared01/Shops/mace/MediaGallery/new_images_10-11-11/Boost_Solenoid_Disable_3.jpg