Octane And The Turbocharged Engine

Fast Friday Volvo Performance and Tuning

Any time you compress air it’s going to increase in temperature, with a turbo charger it’s no different. The more boost you run the more heat is imparted to the air going into the engine. This heat along with latent heat from the previous combustion cycle can increase enough that the fuel can actually ignite before the spark plug lights it off, which is called pre-ignition or ping. Pre-ignition can be very damaging to an engine if it is severe enough or occurs over a long enough period of time. So higher octane fuels help avoid this.

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.

Fast Friday #4 — The Boost Variance Problem

Fast Friday Volvo Performance and Tuning

Boost pressure issues seem to be the #2 issue in the Volvo Performance world beaten out only by vacuum leaks. Boost pressure control in the 1994-1998 models is a pretty simple system but for the ECU to manage boost correctly it relies heavily on known base values and settings. If these settings are off or if there are mechanical issues then the boost control system can be out of whack.

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 […]

Front Mount Intercooler Install

I was close to getting a treadstone intercooler and while they claim to support more power for the money, the precsision IC’s have a much higher quality from what I’ve been told and are better engineered. Besides, I don’t plan on making over 350 whp any time soon anyways so this will do well… and when I do an engine build, the wife’s T5 will get my IC setup.

Recomended MBC for Volvo 850 Turbo

$80 Hallman ES MBC - Manual Boost Controller

Manual Boost Controllers (MBCs) are the cheapest way to get more power out of your turbo. Please do a Stage 0 first! clawless » This link has a good ‘how to’ on boost controllers for Volvo turbos. With the ECU controlling the boost you may not get what you want with a MBC. I plan on […]

High boost cutoff switch

volvo power

if you continue to run your engine with higher than designed turbo boost, be prepared to replace either the engine, transmission, other parts of the drive train or all of the above within a couple years…