• Remove the panel below the steering column. There should be 4 bolt/screws securing this panel. Once removed, the A/C duct to the driver vent should be visible.

• Either remove or set aside the A/C duct (there is 1 screw/clip securing it). Once that is done, you will see the steering column and a metal grate with holes in them directly to the left of the steering column.
• Remove the bolt (12 mm) and the screw securing the grate in place. They should be located towards the top end of the grate (driver side) and the bottom end of the grate (engine side).

• Work the grate free from it's mounting place and you will see 3 harnesses set on the grate on the backside. One of the harnesses is where you will use the harness you have purchased. I believe that it is the one closest to the steering wheel (the harness are of different sizes so only one of them will fit the extra harness).

Once extra harness is clipped in, replace the metal grate as before using the bolt and screw you removed. Do not put everyting back together yet. You'll have to test the timer once everything is hooked up. It will be easier and less time consuming if you should encounter a problem with the install later.

This is probably going to take you a little while. It's a pain in the ass but it's well worth it. You will need to remove the entire center section of the interior, all the way back to the center storage box.

Handbrake Kill Wire

• Remove the cover for the center stereo console. There are 4 screws that are covered by plastic clips. 2 are located in the top corner of the A/C vents, and two are located in the middle of the center panel under a long horizontal piece of plastic. Simply pop those off with a flathead screwdriver.

• If a 5-speed, remove the shift knob by turning the shift knob counter-clockwise. If it's stuck, give the knob a really big yank, it will come free. If you have an auto, you may skip to the next step.
• Remove the panel directly below the center stereo panel you just removed. There are 3 screws holding this down, 2 are located in the top corners on this panel, and 1 on the ashtray area (remove the ashtray and you'll find the screw in the top-left area). Pop the top ends on this panel off and then slide the panel forward. you will have some wires/harness connecting to the cigarette lighter and the mirror and suspension control switches. Unhook those and set the panel aside.

• Remove the center storage box. You'll have to empty the storage box, and pull the carpeting of the box off. There are 5 big screws holding the box down: 3 screws in the box and also 2 more towards the front of this entire piece.

• Your handbrake should now be exposed. Locate the wire to the handbrake sensor (passenger side and toward the back of the handbrake mechanism). You'll have to cut away some of the plastic insulation to expose the wire AND THEN splice that wire to the white wire of the BDTT (the BDTT may not come with the extension so use any 18-22 gauge electrical wire). Here's the diagram, this was taken from a posting on TT.net where a member wrote that the hanbrake was optional. This is true but you will lose this feature if you do not hook it up (basically, you'd be allowing anyone to drive away in your while the timer is active).

There will be two wires that will be spliced to the ECU. This will allow you to use the various functions on the timer such as the tachometer and speedometer features. DISCONNECT THE BATTERY BEFORE YOU DO THIS SECTION!!! Your ECU is located under the passenger foot board. Simply remove the carpet and remove the wooden board. Your ECU is on the left. You'll need to remove the ECU from it's resting position and remove the harness connecting to the ECU. Refer to your instruction manual. Please look at the diagram carefully as the harness is divided into 4 sections of 16-20-20-20 wires. The location marked with a black spot is the wire you will need to splice.

There will be two wires you need to splice to the ECU. If you refer to the English Installation Manual, find ECU diagram for Nissan 300ZX Twin Turbo (90-96). Be very careful when reading the diagram as I've already mentioned the 16-20-20-20 sections. The diagram shows the ECU FROM THE WIRED SIDE and not from the side that plugs into the ECU.

On the diagram:
RPM signal is denoted by the 'I' (find a yellow wire with red stripe).
Speed sensor is denoted by the 'S' (fine a yellow wire with green stripe).

NOTE: Wire colors that you will tap into may not be the same as the ones I have outlined above depending on year. Although in my experience installing countless numbers of timers, the RPM and Speed wires have been the same, this isn't to say that it is always the case (so be fore warned if the wire colors are not the same on your vehicle).

Once you've completed this section, find yourself a suitable location to mount Timer in the car. One of the more common places is in the stock clock location. However, unlike the HKS Turbo Timer III or IV, it's doesn't fit perfectly and you need to do some filing to the clock opening to make the BDTT fit nicely. Also you will need to fabricate some kind of bracket in the back to help hold the Timer in place.

Here are some pics of alternative location to the stock clock locations.

Remember when I told you why you shouldn't put everything back together right away? We need to test it and see if it works first! Otherwise we'll just end up pulling everything apart again if something goes wrong.

Test #1
Start the engine, set your timer to 30 secs. With the handbrake up, remove the key from the ignition. Your engine should still be running and the countdown begins. When it hit's zero, the engine should shut down.

Test #2
Start the engine and remove the key. Timer should count down like in the above test. Now with the foot on the brake pedal (so you won't roll away), release the handbrake anytime before the timer hits zero. The engine should automatically shutdown.

If all of the above works fine, you have successfully completed the install and may replace all the ducts and panels.

Now that you have a fully functional timer, there is a couple of things that needs to be done and that is to calibrate the tachometer and speedometer on the timer. If this is not done, neither will match with your factory tachometer. Calibrating the timer is very easy and is done using the following steps:

For the tachometer (RPM):

1. Turn the ignition to the 'ON' position but DO NOT start the car.
2. Select the RPM or tachometer feature on the timer by pressing the 'M' button as many times as necessary.
3. Once the RPM feature is selected, start the engine. You will notice that once you start revving the engine, the RPM readings on both the timer and the tach will not match.
4. Rev the engine to 2000 rpms and hold it there.
5. Then, while holding the rpms at 2000, simply press the 'T2' button. This will calibrate and set your timer.

1. Turn the ignition to the 'ON' position but DO NOT start the car.
2. Select the speedometer feature on the timer by pressing the 'M' button as many times as necessary.
3. Once the feature is selected, start the engine. You will notice that once you start driving the car, the speedometer readings on both the timer and the tach will not match.
4. Begin driving the vehicle to 40 km/h (or 25 mph).
5. Then, while holding the speed at 40km/h (25 mph), press the 'T2' button. This will calibrate and set your timer.