Very Low Budget Performance

Silly Projects

Water Injection

Well water injection isn't THAT silly, but the way I did it was.

First, some background.

Water injectiom was first used in supercharged aircraft engines, circa World War II. When injected into the intake manifolds it helped to cool the hot intake air and supress detonation (Pinging) which would otherwise destroy the engine. Later this technology was also applied to automotive engines. It was found that in addition to suppressing the detonation in forced induction engines, it would also help in naturally aspirated engines with high compression ratios. As high boost levels and high compression ratios both help to increase total power output, water injection can be a very useful tool in building high powered engines.

So why isn't it used more often?

Well it is too much bother. For a system to be effective it needs to inject a lot of water, so much so that the water tank would need to be filled as often as the petrol tank. For the average car buyer this sounds too much like hard work, so it is not used. However for an enthusiast who is prepared to tolerate extra mantainance for extra performance, that is not a barrier.
It is also a modification that doesn't work by itself. If you get a car that is working fine, and add water Injection, you get no improvement at all, it only helps if the car was suffering detonation in the first place. So it is more difficult than just adding it to an engine and seeing the improvement. Hence less people appreciate it's usefulness.

Nevertheless I was keen to use it in my car. My Statesman was experiencing detonation under load. This was due to

It was burning lots of oil leading to carbon deposits in the chambers. These reduce chamber volume, and hence increase compression. They also get hot and act as secondary and premature sources of ignition. So you can see that they are bad for pinging. It should be noted here that in addition to stopping the pinging, Water Injection also serves to clean out the carbon deposits, thus reducing the need for Water Injection
The Environazi pressure groups had forced the Government to reduce the allowable lead content in leaded petrol. The Oil company pressure groups refused to add more expensive hydrocarbon fractions to retain the octane rating, so the Government caved to both sides and allowed the octane rating to be reduced.

Therefore, I set out to instal some water injection. With a 20c piece of tubing and a garden irrigation sprinkler I diverted the windscreen washer so that it sprayed down the throat of the carby.

This worked! though only at full load. Mind you for detonation suppression you only need it at full load. So when accelerating up a hill I could hear the gentle clink-clink of my pistons being destroyed. I then could push the windscreen washer button and the sound would disappear. There were a few problems though...

Firstly, if I turned the spray on at any time other than full throttle, the excess water would almost stall the engine. As stated above, full throttle it the only time you need detonation suppression, but for cylinder cleaning it is not as suitable. Even at full throttle, there was a distinct reduction in power at the lower revs. (And this was a Holden six, so lower revs were 1000 to 2000 rpm.) The obvious cause was that the irrigation nozzle was dumping in too much water, so I replaced this with the nozzle off a flyspray can, and it worked much better.
Secondly, the button that turned the washer motor on also turned the wipers on. Irritating, but harmless.
Thirdly, to turn the washer switch on required one to take one hand off the steering wheel. Not advisable under full throttle. I tried constructing a throttle switch so that the water Injection would tun on automatically at full throttle, but I never got around to finishing it.
Lastly, and this is the problem with all water injection systems, it tends to use up the water rather quickly. Less quickly when I put on the finer spray nozzle but still annoying in the number of refills required. At least water is free.

Performance Well it worked fine! The detonation was suppressed, and after a few weeks it cleaned up the heads to the point where detonation went away completely. A couple of years later when I got a new engine, it also detonated, so I pulled out the tube with the flyspray nozzle on one end, plumped it in, and soon that engine was cured too.

Nonetheless, if anyone wants to try this at home I have some advice.

Ignore the irrigation sprays and go straight for the flyspray. It produced a much finer mist and is both safer and more effective
Set up some sort of throttle switch, the windscreen washer button is not the way to go.
Try to get a separate windscreen washer bottle and pump for the water injection. Otherwise you can't use your washer to clean your windshield anymore.

Nitromethanol Injection

Once you have a water injection system, the mind starts to contemplate what else could be injected through it. The ultimate that I could think of was nitromethanol.

Nitromethanol is a combined fuel and oxidizer, which offers the possibility of almost doubling the power output of an engine (according to some sources). As it provides its own oxidiser, it can be added in addition to fuel, as well as in substitution for fuel, and indeed is usually used under very overrich conditions (2:1 air:fuel ratio in some cases). Hence adding it to the intake in addition to the normal fuel load should provide no problems.

Use of Nitromethanol injection would be like that of Nitrous Oxide injection, with an electrical trigger resulting in a set increase in power and torque, the increase in power being determined by the size of the nozzles used. The advantages of Nitromethanol would be:

No High Pressures. Nitrous Oxide comes in the form of a pressurized gas, which requires heavy gas bottles, pressurized lines, expensive solenoid valves etc. There is no reason that the nitromethanol would need any more equipment than the water injection, though you might want to get a storage container that was resistant to heat, corrosion and static buildup.
Nitrous Oxide is just an oxidizer, and needs to have sufficient fuel added as well to stop lean conditions from destroying the engine. As nitromethanol is fuel and oxidizer in one, and you would be adding it to an engine already at the correct air:fuel ratio, then you could never get lean conditions. Hence the critical fuel/nitrous oxide controls would be superfluous.
Nitromethanol is widely available at hobbyshops as it is used in model planes and boats as fuel.
As a result of the above advantages, a nitromethanol injection set up would be much cheaper and quicker to set up, would be less likely to damage the engine, and would be far easier to conceal from any enviro/social-responsibility enforcement officers.

So how did it go? Well... I had the injection set up (from the water injection days) I went into some hobby stores and priced the NitroMethanol ($20/litre at Stones Corner, Brisbane) and then...I got a new job and moved to Sydney, selling the car in the process. And I'm NOT keen on trying it with my lovely new car.

So if anyone else out there has some old bomb that they are prepared to risk sacrificing in the name of performance science, give it a burl and tell me about it.

Later

Well I HAVE recieved some replies, including one from someone who tried it out in his Formula Ford. Result: A lot more power, so much so that the car became difficult to control. Sucess!

260 kW Lathe

I know what you're thinking. While a 260 kW lathe sounds like a silly home project, it's not really automotive is it? Well just take a look at the picture. Turning up some wheels

As you can see, the lathe is constructed from a stretched WB Holden ute. You just jack it up, mount a chuck on one wheel and set to work. With the worked 5 litre V8 he has you get an engine power of 260 kW. And 5 forward and 1 reverse speeds. My flatmate (in the picture) set it up so he could machine smooth his second hand mag wheels he just bought.

He then proceeded to run it at about 200 watts because that's all the power you need, but if I ever need to machine down a battle ship drive shaft or something...

Trip Computer

Autospeed

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