Response

Re Easy Bass

Just a couple of quick points with regards to Selecting and Installing a Free Air Sub.

There appears to one big no-no in this article (though, admittedly, it probably won't be audible through a sub amp). You mention wiring the amplifier earth directly to the negative terminal of the battery - you don't do this. Not only is it inefficient in its use of materials (extra cabling - the body will provide far greater current capability than ANY standard wire gauge), but it is very prone to introducing electrical noise into the system. Always earth as near as is practical to the amplifier (you've shown people how to make a decent earth many times - baring the metal, not using galvanised or alloy bolts, and painting to protect the surface afterwards). Another point to note (again, in your application with increased fan cooling, probably not a problem) but you should never mount amps upside down like this. A lot of heat will naturally travel upwards through the PCB rather than into the heat-sink below, causing heat-related failure, de-soldering of the components or even delaminating of the PCB itself. Instead, mount the amp ‘right way up’ on an MDF, plastic or alloy panel (something non-conductive) and use 'stand-offs' and long bolts or threaded rod to mount it to the shelf in the same way.

Again, nothing wrong with your application, but your readers may benefit from this.

Luke Konynenburg
Australia

Liked the Wide Perspective #1

I recently read the Evo through the Eyes of... article. Thanks, it was really good. I think that particular format (ie other people's perspectives on things) is always very interesting - especially to have four different takes. It's fun to read, insightful and tremendously practical. Good stuff.

Nathan Veitch
Australia

Liked the Wide Perspective #2

Re the Evo IX review Evo through the Eyes of - it was a refreshingly different article, altogether different from a review by, say, a motoring journalist who drives lots of new cars but has a Toyota Corolla station wagon as their daily driver. Having the views of regular people who have hi-po vehicles as their daily drivers made this article relevant to me. Keep up the good ideas.

M. Machin
New Zealand

HPVs and AW11s

Congratulations on the Human Powered Vehicle (HPV) articles. They are excellent, informative and thought provoking. Are there any plans to release any diagrams with dimensions (perhaps at a reasonable cost for your time and effort)?

Also, I’m looking at making a water injection set up for my supercharged Toyota AW11 MR2. The plan is to put the nozzle before the throttle body and have the spray go through the supercharger. This, I believe, should be most beneficial as the water would get the most time to evaporate, is on the low pressure side and should help improve the efficiency of the supercharger (small amounts of water helps to reduce internal leakage of positive displacement superchargers). Is there any problem with doing this? As the air then goes through the standard intercooler (‘interheater’), can this cause the water to condense and fall out of the air stream? Or would I need a more effective intercooler for that to happen? Keep up the good work.

Howard Hartman
Australia

Releasing HPV diagrams and dimensions isn’t something we’ve considered – but we will give it some thought. We can’t see any problems with your suggested water injection approach but it’s important to make sure the water is highly atomized for maximum effectiveness. Also, avoid the nozzle dribbling once the system has been activated and then shut off. The standard AW11 intercooler is pretty average in terms of flow and heat exchange ability so a replacement unit would be beneficial.

More on Mixture Meter

I am interested in KC5195: Mixture Display Kit For Fuel Injected Cars AutoSpeed Shop. I am curious as to the directions that come with the unit, if any. I am also curious as to its compatibility with older vehicles - I have an '87 Porsche 911 turbo with the original oxygen sensor and would like to know if that O2 sensor is compatible with your product.

Mark
Canada

Further information on these 10 LED mixture meters can be found at Cheaply Monitoring Air/Fuel Ratios The mixture meter can be used on any 0 – 1V oxygen sensor signal (which is typical for most production cars). Full information (including assembly instructions) is provided with the kit.

Spray Not Okay

I own your intelligent intercooler sprayer (as covered in Intelligent Intercooler Water Spray - Part 1) and I've found it to be very particular about registering temperature readings. Below 55F (12.8 degrees Celsius), the intercooler and outside air temperature (OAT) lights extinguish. When above about 150F (65.6 degrees Celsius), the IC light also extinguishes. Sometimes when the IC temperature rises very rapidly, the IC temp light will extinguish. In each case the system fails to function as advertised when the temperature sensing light goes off. I was wondering if there is some revision to the control logic that corrects these problems. In practice I find that the system only works as advertised about two thirds of the time. It is especially frustrating to see the temperature lights go out under the very conditions where I want the system to function.

Jeff Jones
USA

The first step is to check the continuity of the wiring and all wiring connections. Following that, we suggest contacting the product’s designer/manufacturer – Labtronics – on +61 8 8231 5966.