The world of DIY car modification has just changed…

Posted on February 13th, 2005 in Opinion by Julian Edgar

Well, they’re finally been released! Yes, the cutting edge electronic kits which I seem to have been writing about for ever are now on the shelves, ready and raring to go.

For those of you who haven’t been following events, the electronic projects have been developed by Silicon Chip publications, the company that produces Silicon Chip magazine. (Web Publications, the publisher of AutoSpeed, puts up the on-line version of Silicon Chip.) I’ve worked as a freelance journalist for Silicon Chip for many years, and it was in that role that I helped develop the electronic car projects. The final prototypes were finished about a year ago and I was running working examples in my cars in the year before that – so as you can see, for me they’ve been around for a very long time! (Which is probably why I started writing about them in AutoSpeed too early!)

The reason for the delay in their release is nothing to do with a need to re-work prototypes or anything like that. The wait has a much simpler reason: it’s taken Silicon Chip Publications this long to produce the book which contains all the projects. But now the book is out – it’s called High Performance Electronics for Cars – and all the projects are available as kits from Jaycar Electronics or through the AutoSpeed Shop. (If there is the demand, the kits will also be available fully built and tested through the AutoSpeed shop.)

So has the wait has been worth it? I sure think so! And I don’t say that because I co-authored the book with brilliant electronics engineer John Clarke, but because I genuinely believe that the projects allow people to achieve a range of car modifications which were previously impossible to do simply and cheaply. In addition to the 16 projects, the book also contains really good background chapters on how engine management and other electronic car systems work. The latter are included because with these projects it’s easy to modify auto trans control, power steering weight control – even active four wheel drive control!

The simplest of the kits are those that are generic building blocks. For example, there’s the Frequency Switch (AUD$35.95). I’ve given up counting how many times I’ve seen plaintive requests on discussion groups from people who want to operate a shift-light, or change the switching revs of an active intake manifold. Well, now it’s easy – you can pick up a frequency signal from the injectors, crank-angle sensor, the ECU tacho output or even road speed sensor. And when the right speed is reached, over clicks a 5-amp relay – so you can directly switch lights, buzzers, solenoids….you name it.

In one prototype application I used it to switch on an intercooler fan whenever engine revs dropped back to idle.

Another building block is the Simple Voltage Switch (AUD$29.95). Like the Frequency Switch, it can operate on either a rising or falling signal, and also like the Frequency Switch, not only is the set-point adjustable but so is the hysteresis (the difference between switch-on and switch-off levels). This module can be used to switch devices on or off with an input from the standard airflow meter, oxygen sensor, coolant temp sensor, intake air temp sensor, fuel level sensor, oil pressure sensor – literally, any voltage outputting sensor on the car. That makes it incredibly useful!

In prototype applications I’ve used it to operate radiator fans (the signal input taken from ECU coolant temp sensor) and to switch-in engine management mods above a certain load (airflow meter input).

Then there’s the Temperature Switch (AUD$29.95) – well, you can guess what it does, but you should know that it’ll work at temps of up to 245 degrees C and uses a remote sensor.

It’s also easy to daisy-chain the switches, so that two parameters need to be exceeded before an output is enabled. So for example, you can now trigger an intercooler water spray only when intake air temp and load are both above certain levels.

Of course, it’s also possible to use external sensors with these electronic switches. So for example, with the input of a voltage outputting g-sensor, you can have devices trip only under high accelerations; with the input of a pressure sensor, devices can be switched only above or below certain pressures, and so on.

Start thinking about the uses of these three devices and there’s almost no car modification limit!

I’ll mention just two of the other 13 projects.

The first is the Digital Fuel Adjuster (AUD$79.95). This is a one-dimensional interceptor that takes in the voltage signal from the airflow meter and spits out whatever signal you want. It’s mappable (using a dedicated digital hand controller – AUD$59.95) at over 128 different input voltage levels and can be very finely adjusted up and down at each of those levels. It is ideal for calibrating the air/fuel ratio after airflow meter or injector swaps, leaning-out top-end mixtures and altering mid-range mixtures. In use it works brilliantly, although it must be said that like any interceptor, it does have some limitations.

The uses the prototype was put to? Well, try the recalibration of the mixtures of a 1988 Nissan Maxima V6 Turbo running a huge airflow meter bypass, remapping the top-end mixtures on a 1998 Lexus LS400, altering high load mixtures on a 1999 Toyota Prius, the complete remapping of a 1985 BMW 735i – and further short-term testing on a Nissan 200SX and WRX and STi Imprezas.

The other device is more complex to understand.

Called the Digital Pulse Adjuster (AUD$79.95), it works in much the same way as the Digital Fuel Adjuster but instead of being able to intercept and remap voltage levels, it does the same for duty cycles. It is also different in that it can directly drive the output, for example a solenoid valve. Uses? Well, anywhere you have a pulse width modulated solenoid in action (variable weight power steering, auto trans lines pressure control, factory boost solenoid, extra injector), the response curve can be remapped.

The prototype has been doing duty (pun!) on the power steering of a 1999 Lexus LS400 for 18 months, and another was used to completely remap the boost curve on a 1994 Impreza WRX.

Whew! I get excited just thinking about the possibilities! And that’s not even mentioning kits like the Intelligent Turbo Timer which monitors how hard you have been driving, the Speedo Corrector that lets you fix electronic speedo and tacho errors, and the Independent Electronic Boost Control which takes a unique approach to setting turbo boost pressures.

To see the full range of kits, go to Autospeed Automotive Kits and for the Pre-assembled versions of some of these kits go to Autospeed Pre-assembled Kits

2 Responses to 'The world of DIY car modification has just changed…'

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  1. rishi said,

    on January 13th, 2009 at 10:38 pm

    Hi Julian, I live in Australia, and I own a ’97 Nissan Pulsar Sedan. I love the car, it’s very comfortable, it’s got great handling, great zippy power and I love how the car has a facotry bodykit.

    I’m nineteen years old, and am finally earning some good cash, which I’m saving, and I would love to spend that money to repair and modify the car.

    I won’t bother with the interior right now; I’ve already got a great sound system and the seats are great, but what I would like to perhaps chuck in a new engine: preferably a 1.6 litre inline 4, a supercharger, an exhaust system, better suspension, performance wheels and tyres, and better brakes. Would you be able to tell me whether such a small engined car is capable of handling all that extra power? And given such a small room to operate; I’m aiming to get 200-250 hp out of the car if my mods are successful, do you think its possible?

  2. Ben said,

    on January 14th, 2009 at 8:59 am

    Don’t the SSS models of that year already have an SR20 in them? 250hp is a snack for pretty much any of the modern 2.0 turbo engines (provided they don’t have more than that stock…), so you are probably better off starting with one of those engines.

    Read this series

    250hp out of a 1.6 is possible, but (at least in nz) iit costs less to buy a TT Legacy then it would cost for just the supercharger kit and engine management. And you have a 2.0 Twin turbo AWD thrash car that can also carry your 4 mates, as well as your 1.6L FWD daily runabout. (Twin turbo legacy’s have been seen many times on the market here for less than $2000)