Contributor: Gary Boxall - New Zealand Rover 220GTi turbo

Gary wrote: Following the increase in boost pressure, I was still a little concerned about retaining reliability. After all, the T series engine isn't exactly the strongest in the world. The last thing I wanted to happen was piston failure due to excessive cylinder temperatures caused by the increase in boost pressure. However, all was not lost - there was a ready made solution. It came in the form of a water injection kit from Aquamist. The basic idea is that a very fine spray of water is injected into the intake system. This 'atomised' water absorbs heat and at the same time acts as a 'coolant' inside the combustion chamber. It may seem an odd thing to do, adding water to the combustion chamber but it is a very effective method of cooling. It does not reduce the combustion of the air / fuel mixture. It is even used by WRC cars - a fine testimony indeed. A few years ago I 'dropped' a T16 turbo lump into an MG Montego turbo and amongst the many modifications I carried out, an Aquamist water injection kit was installed. It gave sterling service and peace of mind. It also effectively dropped the intake  temperature to such an extent that the car felt a lot more responsive on boost.  Armed with this previous experience, I placed an order for the System 1 kit which promptly arrived one morning. Several  changes had been made to the kit which I had previously purchased and they are definite improvements which makes  installation pretty easy.    The System 1 kit which I used. A very comprehensive kit which contains virtually everything needed. Minimal tools are required and the instruction sheet is very clear and precise making this a relatively easy installation. The water injection is triggered by a manifold pressure switch. When activated, a current is sent to a relay which in urn  activates the pump. The wiring loom supplied is self-contained and is the first part of the installation. Placement of the parts,  once again, comes down to personal preference and space available. I positioned the relay (right) behind the near side headlight, utilising a mounting point for the fuse box bracket. Being within the confines of the cold air box, it would be well protected too. The pump requires an ignition +ve supply and the loom's purple wire was connected to the ignition coil feed wire. This is the brown wire with a pink tracer. I simply cut the wire, twisted the end of the purple wire together and soldered them. Finally, a piece of heatshrink completed the job. The next job was to connect the main power feed. I simply used one of the spare terminals on the DC power distribution I had installed when I positioned the battery into the boot. The earth was bolted to an OE point on the slam panel. I then turned my attention to fitting the manifold pressure switch. A mounting bracket is supplied and I chose to mount this on the bulkhead. Two holes were drilled and the bare metal liberally coated with paint. The bracket was then screwed into place using the supplied self tapping screws. The switch was then mounted on the bracket and the pressure hose was tapped into the boost gauge circuit using the supplied T piece. You do not have to use the boost gauge circuit (if fitted) as any point is suitable, so long as it can sense pressure in the inlet manifold. With the switch in place, the wiring can be connected. Note that there are two wires connected to the spade connectors instead of the usual one. This is to allow me to fit an LED which illuminates when the switch is activated. Full details on this can be found on the ERL website. The pressure switch is adjustable by means of a screw (circled). The pressure switch is factory set at 10psi and can be altered to suit your application. I chose to alter it to 8 psi. With the wiring connected, the supplied protective boot can pushed in place. The rest of the wiring was then routed around the engine bay to tidy everything up. You will now need to decide where to mount the water pump. For effective operation, it should be at the same level or lower than its water supply. I chose to mount it inside the cold air box because there was plenty of space and it would offer the pump protection from the elements. Nuts and bolts are provided for mounting. Note the self contained harness with the multiplug. This simply connects to the main loom. Next, the intercooler was removed so I could fit the water jet. I would NOT recommend doing this step with the intercooler left in situ as the risk of swarf entering the intercooler is high. Note that I have inserted a damp rag into the end pipe to help catch the alloy debris. Once a suitable hole has been drilled, the hole is tapped with the supplied tap. The unit was flushed out to ensure no debris was left in the intercooler and the water jet screwed into place. There are 3 jets supplied with the kit - 0.5, 0.6 and 0.7. The amount of water injected obviously depends on the jet size. For further information you should check out the ERL website. I opted for the 0.6 size jet. With this in place, the intercooler can be refitted. The water pump / cold air box assembly can now be refitted too. Once in place, the pump harness is plugged into the main loom andI have secured the plugs to the underside of the slam panel with a P clip. The jet is then connected to the pump by using a length of the supplied 4mm nylon tubing. As I previously mentioned, the water pump should be mounted lower or level with its water supply. Due to the position of the OE  washer bottle (below the inner wing), it was impractical to mount the pump that low down. So I decided to make a new water reservoir  tank which would fit in the inner wing above the OE washer bottle. I started by making a mock up from modelers plastic card and when I was happy with the final design, had a copy made from stainless steel by a friend. The completed tank. It is held in place by brackets which utilize existing mounting points - power steering fluid tank bracket and a pipe clamp on the bottom. The take off point for the water is on the bottom front edge of the tank. The hole has been threaded to accept the supplied water filter. A mix of 80% water and 20% Methanol is used to prevent the water freezing. The final job is to connect the reservoir tank to the water pump. 6mm nylon tubing is supplied for this purpose, but I decided to make my own pipework. I simply used some aluminium tubing which runs between the headlights and sits just behind the grille. This way, it allows the water to cool while passing along the tube before reaching the pump. The picture on the left shows the aluminium tube connected to a rubber hose which I had in my spares box. It is secured at both ends by means of a nylon P clip which is screwed into an existing hole. To the right shows the rubber hose connected to the supplied 6mm nylon tubing using a short piece of aluminium tubing. This was done as the pump and the filter are designed to be connected using the supplied hose. The connection is once again secured with a P clip and attached to an existing mounting point. The pictures depict the water pump end of the pipework - the same set up was used at the tank end. Before taking the car for a run, the system was checked to ensure it ran. Firstly, I disconnected the pipe between the pump and  the jet. The ignition was switched on (it is not necessary to have the engine running) and one of the spade connectors was removed from the pressure switch. The pump should run and water will spurt out. If it does not, check all you connections to ensure you are not entraining air. If they are all okay, you will need to pressurize the water system to help with the water flow through the pump initially. Once it starts to come through, you can depressurize the system and the pump should now work effectively. Next, run a length of 4mm pipe from the pump and wedge it under the windscreen wiper with a spare jet pointing towards the screen. Take the car for a drive and when you come to the pre set boost pressure, the pump should be activated and a very fine mist of water will be sprayed onto the screen. Once you are happy with this, you can either alter the pressure switch by using this method or have it set up on a rolling road. Job done. At the time of this page being uploaded to the website, I have yet to take the car to the rolling road to see what difference it makes to the intake temperatures. When time permits, I shall being doing a back-to-back test and the results will be published here.

Finally, very special thanks to Richard Lamb at Aquamist and John Prangnell for making the tank. Watch this space for further reports! Gary Boxall       or visit       www.rover.org.nz/220gti July 2001