Just bought a 98 gtp for cheap. This is my 4th one and I have a little idea of what's going on here but this car has a aftermarket pulley (how do I figure out what size) it has slp headers and a new cat and ubend delete I believe 180 tstat because that's what temp it sticks around. What kind of plugs should i be getting...But here's the problem. First off no boost... I tried looking for a vac leak cuz when the car is in park and u give it a little gas when the rpms drop it dips down to about 500rpm and sounds like it wants to die.. It doesn't ever die but it just about does... So what's the best way to search for a vacume leak.. I did by hand and didn't see anything noticeable wrong... Also I thought maybe the bbv is bad so I will be playing with that tomorrow.. Any other ideas? My stock Lego guage only says about half boost and this thing feels like a stock gt..