3.3TT Stock Turbo/Intercooler Efficiency?

[Hyperjetta]

I'm wondering if there is any data out there on intake air temperatures at different points in the intake components. With the on board sensors we can see the ambient air temps and the intake air temperature at the charge pipe coming out of the intercooler. Ideally I'd like to see the air temps just before the intercooler as well to better understand the efficiency of the stock setup.

Assuming that this data doesn't exist, I'm curious what would be the best way to measure those temps. I've seen some different temperature sensors available online, but I have no experience with how to set something like that up in such a way as to log it.

 

[Manaz]

You'd have to get temperature sensors into the airflow, ideally the same kind/configured with the same accuracy.

Another benefit.of having a pre-intercooler temperature is that you will also know how efficient the turbos are.

 

[Hyperjetta]

You'd have to get temperature sensors into the airflow, ideally the same kind/configured with the same accuracy.

Another benefit.of having a pre-intercooler temperature is that you will also know how efficient the turbos are.

I am planning to set up an arduino with a k type thermocouple sensor tapped into the hot side line somewhere. The plastic intercooler inlet seems like it might be an ideal spot since it's easily accessible and would be easy to drill.

I'm not sure I have the maths to do this, but I'm gonna go down swinging.

 

[Manaz]

The maths is the easy bit

 

[Hyperjetta]

I did a test run after getting everything installed and set up so I figured I'd throw my data and such up here for critique. This a very small sample, but its enough to get the idea of where I'm headed. This is running the stock intercooler and map 0 on the JB4. I will try to get some longer logs in various conditions over the next few weeks.

For those interested in how I'm getting the data:

I am using an Arduino Uno with the Seeed Studio CANbus shield for the interface to the OBD2 port and a Max6675 thermocouple amp to convert the temperature coming from a k-type thermocouple sensor I installed in the plastic housing of the intercooler inlet. The sensor tip is positioned perpendicular to the flow of air, and is roughly centered in the pipe.

Aside from the custom sensor, I am pulling the following from the ECU over the OBD2 port:

• RPM
• Vehicle Speed
• Boost
• Intake Air Temperature
• Atmospheric Pressure
• Ambient Temperature

Finally, all of the data points are logged to the SD card on the CANbus shield.







FYI, I pulled out some of the data points in the charts where I felt it was muddying things up, such as when the car wasn't moving, or when there was no boost being generated by the turbos. I've included the raw data with the extraneous data for those that are interested.