CAN ANYONE PROVIDE ANY SUGGESTIONS/THOUGHTS ON THE FOLLOWING
Mods
• Fuel pump (Walbro 500hp, 250l/h), I/C(Blitz LM kit), turbo (Garrett GT3040), injectors (555cc Nismo), coils (Spitfire), Apexi PowerFC computer, exhaust (Nismo 3.5”), EBC (Greddy Profec B).
Problem Description
• Knocks under load and especially on high boost
• Doesn’t seem to produce power quickly enough – very lathargic
Work Completed
• Replaced upper O2 sensor – improved fuel efficiency but no change in knock
• Removed and inspected all pieces of exhaust for problems. Ran/drove car with exhaust disconnected from dump pipe back – no change in knock.
• Removed piping on inlet and outlet of intercooler for inspection for excessive oil and/or rag left in piping – intercooler and piping both extremely clean, no signs of any oil at all.
• Performed pressure test using smoke machine from just before throttle body to just after AFM – no leaks and held pressure above 1bar.
• Checked PowerFC hand controller coolant temperature sensor reading from cold to operating temperature – nothing seemed unusual.
• Completed compression test on all cylinders – all cylinders +/-3psi.
• Spark plugs changed 3 times – Iridium then copper then copper. No change in knock.
• Fuel pressure has been checked on a dyno run very recently – nothing unusual. Fuel filter replaced anyway.
• AFM – originally installed Z32 replaced with seemingly working Z32 (both purchased brand new).
• Turbosmart BOV (kit for Skyline) – purchased recently just in case it was the standard BOV resulting in the lack of power / lethargic build of power.