Fast Friday #6 — Injectors, MAFs, and Power pt. II

Fast Friday Volvo Performance and Tuning

As performance levels rise so too do the necessary supporting components of the engine to reach the power goals you might have. Most fuel system upgrades are pretty straight forward and only consist of a fuel components I.E. Fuel pump, Injectors, and fuel pressure regulator. For the most part the Walbro series of fuel pumps are a popular cost effective option when it comes to replacing the factory pump.

How do Volvo turbo control valves (TCV) work?

When they fail, how do they fail? Its a pulse modulated solenoid. So it opens and closes like a fuel injector to get the right boost characteristics throughout the entire rpm range.  No air is lost in these systems. They tend to fail with the red and blue open (no boost) but most are replaced […]

Tightening up the Turbo Waste Gate ?

Wastegate Settings – Numbers and Theory The idea here is to assure the wastegate valve remains closed until the wastegate experiences the preset pressure in the VADIS doc above. Anything higher than the Vadis pressure and the wastegate valve shoud move/open. I have a magnetic dial gauge I use to monitor the wastegate valve action […]

Boost for a Light Pressure Turbo

How much Boost for a Light Pressure Turbo? I wouldn't go over ten pounds of boost on it. I have a 850 GLT and right after I put my boost controller on I over boosted and blow my head gasket and had to replace 5 valves. But since then I've been pushing about ten pounds […]

Lost PSI on Turbo Boost

How to Isolate Low Boost Problems Usually if your wastegate is stuck open you wouldnt get 12psi. So, id say thats not the prob. but, what makes me wonder is when you disconnected the vac line to the wastegate why you didnt get more than 12psi. When i disconnect mine and i have a stock […]

Proper Boost Measurements

Warm Idle: 18 inches of mercury vacuum.
Cold Idle: 16 inches of mercury vacuum.
WOT (Wide Open Throttle) 2,000 RPM: ~5 PSI boost.
WOT 3,000 RPM: ~15 PSI boost.
75mph @ 3,000 RPM: ~10 inches of mercury vacuum.
Between Shifts: 0 (atmospheric) due to the bypass valve venting manifold pressure to keep the turbo spooled.