Added some gauges to the car. I used to have these in the Passat
Blue illumination in the Audi not much good as the gauges are white, so needed to convert them to white.
Took the Boost gauge apart and found that the illumination is with surface mount LED chips, so measured them up and ordered some white ones off fleabay.
Original blue LEDS
New white LED's
Those observant people among you might notice that it had 5 blue LEDs and has 6 white LED's. When I fitted the white LED's they were very bright, So I put a resistor in the feed wire and they dimmed, however one of the 5 LED's was still very bright. The LED's were wired in series pairs with a current limiting resistor across the supply. Because the 5 original LED's were set up with the correct current limiting resistors to work on 12V the odd one wasn't an issue. Now I have introduced an extra resistor they are inbalanced. So I replaced a current limiting resistor with an LED on the odd LED which now made it 3 pairs so the illumination was even.
Fortunately Audi made it really easy to pick up a boost tap point by putting a removeable brass plug in the inlet manifold. An 8mm x 1mm 90 degree pneumatic fitting was perfect and then ordered some 4mm plastic air line and this runs straight to the gauge. Very quick , very tidy.
Fed the air line into the car through the ECU box passing through a hole in the boot. Just need a little silicone to seal it.
The EGT gauge sensor was planned to go into the hole where the EGR pipe connected to the turbo. As the EGR has been disabled when it was mapped this seemed to be the best idea, however the pins on the EGR pipe were pretty much welded in and wouldn't budge. So reverted to plan B and the EGT sensor is in the DPF at the moment replacing one of the sensors that used to be used to measure DPF temps.
Not the best place for it as post turbo you don't get proper readings due to the temperature drop across the turbine.
Response is also slow.
Looking for an alternative location pre turbo possibly using one of these clamps if I can find one thats sold in this country.
Amazon.com: Exhaust Gas Technologies Inc. EGT-0335 EGT Probe Sensor Clamp-on Hardware Stainless Steel NEW #32 Clamp: Automotive
The exhaust pipes that feed from the manifold to the collector on the turbo are a nice round stainless pipe that this would fit too well. I could put the EGT sensor in the pre turbo location and remove the factory one but there is a protection map that monitors the temperatures and cuts the fuel should it get too hot. We found this when mapping so had to tweak the temperature up as the factory limiter is very conservative.
I fitted the gauges into the RHS of the centre vent. I bought a complete centre vent from Flea bay to hack only £12 so I can keep the original to swap back at any time to restore the original appearance.
Boost gauge works great, reads within about 0.5 PSI of the MAP sensor. EGT does give you an indication of whats going on and from what I can see logging EGT's on the car the location where the EGT is mounted results in readings about 225 degrees C lower than actual turbine intake temperatures when really on it.
It appears the GTB2260VK is good for 850 degrees continuous all day every day, but short term can be taken upto 900 degrees plus.
Indeed looking through some of the tuning threads people have runs theses at 1000 degrees for several minutes and not had an issue. Flat out about 4K RPM the EGT temperatures are just creeping above 850 degrees. Below 4K RPM they are good.
Karl.