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Just to infrom you guys of the Meth kit options. The unit Kenny has is quite different to any of the cooling mist options. Here are the options commonly used on the BMW platform:
* Basic kit with no integration to tune. This system is completely independant of the tune with no failsafe. Normally consists of a controller that ramps a pump up between low and highs speed between two configurable boost settings. Typically used with tunes that cannot support a failsafe (flash tunes or stock).
* Basic kit with failsafe. Similar to above but adds failsafe that is input into the tune. The failsafe is a signal used by the tune to make the tune more aggressive when meth is flowing, and to pull the tune back to safe if the meth stops flowing for any reason. This is the most common system currently in use and is representitive of the typical cooling mist/JB setup. It is also the system that was initially sold by Vishnu as the gen 1 system using Labonte meth parts.
* Flow controlled by tune. Similar to above, but instead of the controller having two boost settings for min and max flow, the tune outputs a signal that the controller uses to set the pump speed. This has a big advantage that when using big jets, as you can reduce the meth flow at low RPM and increase it at high RPM reducing the effects of meth quench/bog, and reducing meth usage. This is a fairly new thing from BMS. Not sure how many people are using a system like this. I do not believe many (if any) of the Aussies are using it.
* PWM. This is the system Kenny is running. This system is quite different in the hardware to any of above. The primary difference is the presence of a high speed solenoid that is pulsed like a fuel injector. The pump is run at full speed all the time in boost. The meth flow is controlled in the same way as a fuel injector controls flow. The tune sends a high frequency duty cycle waveform that completely turns the flow off when the solenoid is off and runs max flow when it is on. By tuning a map inside the tune you can set the duty cycle of the signal for any desired flow at any operating conditions. At 50% you get 50% flow even though the pump has full output pressure. As with fuel injection, the benefit of this system over above is that you get good atomisation of the meth as the pump is always running at full output pressure, but you can still reduce the meth flow at low RPM in a highly accurate and repeatable way to avoid meth quench/bog and reduce meth usage. This sytem is currently only available from Aquamist, and the Vishnu Meth uses this Aquamist system in there latest gen 2 meth system. In addition, the system also include a new type of flow sensor that is very compact and reliable with minimla moving parts, and can maintain reliability in 100% meth that is used for failsafe.
So that is a description of the differences in Kenny's meth upgrade. Of course all the meth systems are capable of similar power outputs as evidenced by Kenny's car making similar power to previous with the new system. The new system however will use less meth on average, and will benefit more from the meth in the light to medium loads for better drivability due to more accurate meth flow control and better meth atomisation.
Adrian
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