Increasingly recently, people have
started to install turbo speed sensors to monitor the rotor
speed of their turbochargers. I’m not sure if the goal here is
more data to monitor spool, configure antilag or just to make
sure that you’re not overspeeding the turbo, but many people
have asked for the ability to measure turbo speed and record
it on the ECU, so we’ve added it for some specific types of
sensors. The ECU supports up to 2 turbo speed sensors so that
you can measure the turbo speed of two separate turbochargers.
If in the future we build the turbo speed into either exhaust
back pressure monitoring or part of the boost control
algorithm, then turbo 1 will correspond to the odd bank, or
the front half of the engine in a twin-turbo inline 6 eg the
RB26DETT, and turbo 2 will correspond to the even bank or the
rear half of an inline. The inputs that can be used have to be high speed
frequency inputs; so normal digital inputs or analogue
inputs are not suitable. These are:
CAS2, if you’re not using it already for part
of the engine triggering
CAS3, if that’s not being used for the engine
trigger or flex fuel
CAS 4 or 5, if a Mini RT input module is
installed
Flex / frequency input on the Mini RT module
Any of the 3 VSS inputs on the Mini RT module
The main VSS input, if it’s not being used for
vehicle speed.
The selection of the source for the input is made on
the Turbo speed sensor setup page. The type of sensor should also be selected.
Currently we support the following options:
Borg Warner EFR, 67mm compressor (with 12
blades). In this case, the sensor outputs 1 pulse for
every 8 blades, which means that the sensor gives out 1.5
pulses per revolution
Borg Warner EFR, larger than 67mm compressor
(with 14 blades). Again in this case the sensor outputs 1
pulse for every 8 blades, which means 1.75 pulse per
revolution
Honywell / Garrett with a bar type trigger, ie
2 pulses pre revolution
The above sensors all give a digital output, so the
ECU must have that input selected as a digital input. Once the turbo speed input has been selected, it
will appear in the main gauge window and of course you can add
it to your own gauge page or to the monitor panel on the right
hand side, use it as a variable in your built-in scope to
watch spool rates and so on. Thank you.