 |
 |
||||||||||
 |
 |
 |
|
||||||||
 |
 |
 |
|
||||||||
 |
|
||||||||||
 |
 |
 |
 |
 |
 |
 |
|
||||
 |
 |
 |
|
||||||||
 |
|
||||||||||
| |
|
|
|
|
|
|
|
|
|
|
|
| Current best dyno power figure: |
| 218.7 kw @ rear wheels |
| Current best quarter mile: |
|
15.0 seconds @ 98mph |
| Advertisement: |
| |
|
||||||||||
| |
|
|
|
||||||||
| |
|
|
|
||||||||
| |
|
||||||||||
| |
|
|
|
|
|
|
|
||||
| |
|
|
|
||||||||
| |
|
||||||||||
| |
|
|
|
|
|
|
|
|
|
|
|
| Current best dyno power figure: |
| 218.7 kw @ rear wheels |
| Current best quarter mile: |
|
15.0 seconds @ 98mph |
| Advertisement: |
This page details the installation of a digital inlet temperature display, as shown in the Autospeed article: LCD Temp Display!. It is recommended that this article be read first as the idea for this came from that source. This page however goes into further detail in installing the unit in adapting a constant ignition circuit based power supply thus turning the unit on and off automatically and negating the need for batteries.
Items required
As shown in the picture the following items are required (although some are optional). Their relevance is stated in the text below.
The LCD Temperature Display (cat number XC 0224)
The base unit is available from Jaycar for $39.95. It has a temperature reading range from -50 degrees C to 150 degrees C, which should comfortably cover the temperature of inducted air from a car. Other features include high and low temperature warning buzzers and the ability to display temperatures in degrees F. More information is available from the Jaycar website and the above referenced article.
Versitile Voltage Regulator Kit (cat number KA 1797)
This is what is used to change the cars 12V+ down to the 1.5V required for the display. It is a simple kit to make and from memory costs no more than $10. One problem is the the supplied components only allow it to regulate voltage to 3V, so another component is required:
270R Resistor
A pack of these will set you back less than a dollar, and you only need one. One of these is substituted for the supplied resistor in the Voltage Regulator Kit.
Male to Female RCA Cables (optional)
I used these so that the unit could be plugged in and out of the car, which is really handy if you need to change the position of the display unit, as no permanent wiring needs to be cut and rejoined afterwards. Some crimped speaker terminal style connectors would also do the you nicely.
Extra Speaker Wire
This is to extend the wire between the probe and the display unit, which is only 1m long. Obviously more is required to reach from the cabin to the front of the engine bay. K type thermocouple wire was recommended, but I found ordinary speaker wire sufficient.
Construction
The first task to be done is to construct the Voltage Regulator using the instructions provided in the packaging, but with a few alterations. The kit is set up so that a series of resistors is installed with a jumper to select between the required voltage. If you are constructing the kit solely for this purpose like I was then all you need to do is install the 270R resistor as shown ion the picture below, and the unit will be fixed at around 1.5V DC.
The second alteration is to solder on one of the male RCA plugs onto the input voltage wires. If this step is not taken then these wires will go directly to the 12V ACC power supply in the car.
Note that the constructed board has been thoroughly insulated with tape and heat shrink. With the constantly jiggling environment of a car it pays to keep the electrical components seperated to prevent short circuits.
Next the battery is removed from the display unit and the output voltage wires from the regulator are soldered onto the terminals. So thus far the system is set up so that a voltage is received from the car at 12V and is regulated with the adaptor to 1.5V which is then directly connected to the display unit. The terminals of the display unit are very fragile so it is a good idea to coat them in sort of silicone material to suspend the joints in a medium where no stress is placed on them. Hot glue works very well, as when it sets it preserves the joints but can still be peeled off at a later time with some care.
Next cut the wiring for the probe and solder on another colour male RCA plug. Make sure you pay attention to the wires so that the polarity is correct when the wholw system is plugged together, otherwise some very strange reading will be shown. At this point in time it is a good idea to join the speaker wire onto the probe and then the female RCA plug onto that. Also find a suitable ACCESSORY 12V circuit in the car and join in some wiring attached to the last female RCA plug.
Now you must find a suitable mounting spot for the temperature probe. On SR20DE(T) equipped cars the factory induction pipe that either runs to the intercooler or the airbox has a factory blanked hole just before the throttle body. When you remove the pipe you will find the hole has a metal thread and then solid plastic inbetween it and the internal cavity. As the probe is very light it is only neccessary to drill a hole slightly smaller than the metal probe diameter through the plastic, and then slide the probe in. With the right sized hole, it should be a very tight fit and reliable. The picture below right shows the probe pushed into place. Ensure that you very thoroughly clean any debris from the pipe as they will be sucked into the engine otherwise!
Now everything is in place all you have to do is plug everything in. The corresponding plugs for the power supply for the display, and then the connection for the probe. If wired corrrectly, the unit should turn on with a beep as the the is put to the ACC position, and thus will always be on when the car is running. If you wished it to be always on, you could alternatively wire it to a constant 12V source. Enjoy!
Future Update
After the new front intercooler is installed, I will obviously have to reattach the probe, this will be covered at a later date. I plan to use a double display using two units to display the temperature both before and after the intercooler. Watch this space...
