Startup Kit for higher power levels
The nice thing about 745i tuning is that the user can select many different levels of performance. One does not have to spend a lot of money in order to get started with considerably higher power and torque levels.
The most economical and easiest way to get started is the Motronic Chip Upgrade. In addition you only need a turbo pressure gauge and a simple valve to restrict air flow to the Waste Gate control hose (do not bleed the hose for higher boost!!!). Total cost is about 300$. This is a good way to start and to get the feeling of considerably higher power and torque. In this set up you should limit the boost to about 0.7-0.8 bar (300-330 hp/450-500 Nm) if you do not have a rising rate fuel regulator and a fuel/air mixture monitor.. You can install the valve close to the Waste Gate or into the cockpit (this is recommended as that same valve can then be used with the adjustable Waste Gate, if you decide to upgrade). This setup is not ideal solution, but very useful to start with. The max. full throttle boost in this set up is about 0.6-0.7 bar giving 0-100 km/h acceleration of approx. 6.3-6.5 s., which is already an exellent figure for any automatic sports car. More importantly, the middle range boost is about 0.7-0.9 bar giving tremendous acceleration in the 60-160 km/h speed range.
Go to the Wastegate section for detailed descriptions of alternative ways to tune your engine!
|So, this is what you need:||
|1. Chip Upgrade. Follow instruction in these web pages||
|2. Some kind of air valve||
|3. Turbo gauge||
You can use any suitable off-the-shelf pneumatic valves available from your
local hardware store or car tuning companies in your area, or you can buy one
from the Internet, where there are plenty of choices available. We do not recommend
non-pneumatic valves, like fuel valves for snowmobiles, because those tend to
leak pressurized air. You may use those in the upper side (of the modified wastegate)
pressure control, as the function on that side is different.
The air valve can be installed either close to waste gate in engine room or into the cockpit for quick manual power adjustment. In cockpit installation you lose some throttle response time due to long hoses, but that is not a major issue compared to the benefit of having instant manual adjusment of power levels.
You can install the air valve in two different ways:
1. Close to waste gate in the engine room.
This is very economical and fast way as you do not need long hoses and the valve can be any simple air valve, that you can adjust in steps from full open to full close. The draw back is that any change in adjustment requires a stop. Note that the turbo boost level goes up or down at different ambient temperature, relative humidity and air pressure conditions at any given valve position. So you may need to make quite frequent adjustments to the valve position if you want to keep the power level constant. You can also buy special valve kits for boost control. Here are some examples:
|Universal Boostvalve Kit from Boostvalve is available at $39.||
|Super-Duty Boost Controller Kit from www.dawesdevices.com is available at $35 or at $50|
A good choice is VDO Cockpit series no: 150.053/005/002 (Bar scale, I don't
have the order code for PSI scale). Diameter 52 mm, installation depth also
Good place for installation is below the ashtray. You can either use a special instrument cluster ( for 4 gauges) as shown in the pictures, or just replace the left side c-casette rack with a black plastic plate and install the gauge in the plate, if you don't want to install all the gauges right away.
Note that the single air hose to the turbo gauge can be quite thin. You can connect it anywhere in the intake manifold area. The example picture shows how it is connected to the fuel regulator air hose with a T-bar connector. Look at our Gauges section for more options.
Always when you increase the boost levels above 0.7 bar (10 PSI) we recommend to use one step "cooler" spark plugs. E.g. NGK BP5ES instead of standard NGK BP6ES.
Note that you can find really a lot information of these
kinds of boost control systems in the web. Many boost valve manufacturers give
good theoretical info of the boost control system. There are also many interesting
practical examples like
this article from Australia in AutoSpeed pages about similar boost control
system for Audi S4 Turbo.