I have GSC 264/272 cams, 650 injectors, logic upper and lower intercooler pipings, walbro pump, HKS DP, UR 3" high flow cat, HKS cat-back, and a bunch of other mods. New sparks (NGK Iridium), ARp studs, new air filter, etc etc. I only for 314 hp to the wheels and 334 torque. I also got an HKS EVC V spiked to 23.5 psi then tapers to 20 psi. I think I got boost leak. At redline i am losing 2 psi. Where the hell am I losing boost??? Al says I should pick up at least 10-15 hp when I fix the leak.

Car runs strong. Lots of fun but the numbers dont look enough to me but the drive has more than enough.

 

Are you loosing boost or is it just boost taper? Get a 10.5 hotside to help with boost taper.

 

i think i am losing boost.

 

So, you spike to 23psi then it keeps droping to about 18psi by redline? Sounds like boost taper to me. What kinda tuning managment do you have?

 

I am having a similar issue....i can;t tell if it is heat related or a boost leak. I;m running vishnu Xede stage 0+ and am seeing quite a bit of boost taper....spike to 21 then down to 17-18 near redline.