Thread: low boost on gtp

I have a 98 gtp with 3.4 pulley, cai, 104's,zzp 1.0, slp headers w/ no cat or resonator, 3'' dp, msd wires, tb spacer, 180 thermostat, and aeroforce gauge. My question is this i bought the car with alot of the mods already done and havent seen over 4 psi max. When i fist tore into it i realized the tensioner had alot of play in it so i just got a new tensioner with a new 66'' gatorback belt. i also put in all new 104's. whoever had the car before me knew what he was doing when it came to mods. But anyway after replacing the belt i still can only get it to spike to 4psi at the shift point or sometimes lower in the rpm range. i checked the vac lines for leaks (with a can of carb cleaner) but couldnt find anything. im getting 0 kr, but i still cant figure out why im only gettin 4 psi. the car only has 85,000 on it and has a new snout on the supercharger. Any suggestions? Please Help!!

im going to order the new bbv and all new vac lines and fittings just to make sure. but also i was watching my long trim on the scan gauge this morning on my way to work and at 70-100% throttle im +16.4 and when im crusing 70mph its at 10.8 is this bad??

also i have had some serious issues with the flex joint on the exhaust. the one that was welded on by slp is done and leaks bad. getting a new one today gotta good deal on it and it will be in over the weekend, dont think it will rob me 4psi but figured i throw it out there

long trim is the 16.4 the short trim is bouncing all over the place low and high. but i read on here that you can't really ever get the short trim to measure right so i watched the long trim

You just ruined your only hope at ANY fuel economy right there while cruising....