hey guys so i installed my 3" downpipe, boost and afr gauge today as well as my fuel cut defender. car runs great afrs are fine a bit on the rich side but my main problem is when i hit full boost around 4500 rpm im only getting 5psi i checked my gauge with a compressor and it has been t'd to the map sensor vac line that connects to the intake manifold so its accurate and at idle (700rpm) im pulling -10 vacuum and when cruising around the normal 2500-3000rpm range im pulling -8 vaccume any ideas for why im not even hitting stock boost levels thanks!

 

First things first, you need to go over everything you did and make sure you installed everything correctly...it's possible there is a boost leak somewhere in your system so definitely check the area you tapped into for your gauge. What vacuum hose did you use for the source?