John Loudon - Sponsorship Liaison Posted July 18, 2012 Share Posted July 18, 2012 Traction control? Quote Link to comment Share on other sites More sharing options...
fatbaldbloke Posted July 18, 2012 Author Share Posted July 18, 2012 Traction control? Nope Give us a clue? More useful on the road than on track... Quote Link to comment Share on other sites More sharing options...
Dave Eastwood (Gadgetman) - Club Chairman Posted July 18, 2012 Share Posted July 18, 2012 You've fitted parking sensors Quote Link to comment Share on other sites More sharing options...
XTR2Turbo Posted July 18, 2012 Share Posted July 18, 2012 remote relay / immobiliser switch to the fuel pump? Quote Link to comment Share on other sites More sharing options...
fatbaldbloke Posted July 18, 2012 Author Share Posted July 18, 2012 remote relay / immobiliser switch to the fuel pump? nope Quote Link to comment Share on other sites More sharing options...
XTR2Turbo Posted July 18, 2012 Share Posted July 18, 2012 Tracker? Quote Link to comment Share on other sites More sharing options...
fatbaldbloke Posted July 18, 2012 Author Share Posted July 18, 2012 Tracker? Nope, another clue....here's a photo of it wired up Quote Link to comment Share on other sites More sharing options...
adamnreeves Posted July 18, 2012 Share Posted July 18, 2012 Very mysterious. It has four wires, one is a supply (red), no idea what the other wires are for, maybe one is a ground but there are no black wires. Is it wired into the fuel tank sender or is it just tie wrapped to it? Anything to do with lights? Quote Link to comment Share on other sites More sharing options...
Norman Verona Posted July 18, 2012 Share Posted July 18, 2012 I know, I know he cried, waving his arm in the air. It's a box of wires. Quote Link to comment Share on other sites More sharing options...
KugaWestie Posted July 18, 2012 Share Posted July 18, 2012 Is it a gizmo that makes all the lights on the rear light up when you brake? Quote Link to comment Share on other sites More sharing options...
Dave Eastwood (Gadgetman) - Club Chairman Posted July 18, 2012 Share Posted July 18, 2012 Wires seem to follow across the top of the tank and drop down behind the diff. Could go to the fuel pump area, some kind of pump control, or pressure sender down there. Or could go back towards the diff, for some kind of speed sender? Quote Link to comment Share on other sites More sharing options...
fatbaldbloke Posted July 18, 2012 Author Share Posted July 18, 2012 I'll reveal all over lunch... ooh er missus.... Quote Link to comment Share on other sites More sharing options...
Jenko Posted July 18, 2012 Share Posted July 18, 2012 Inertia switch? Or Indicator buzzer? Or Transponder? Or Actully, dunno, can't think of anything else :-( Quote Link to comment Share on other sites More sharing options...
fatbaldbloke Posted July 18, 2012 Author Share Posted July 18, 2012 The Reveal: The problem was that I wil be using the car mostly on the road, so I need a fuel gauge. However I didn't want to spoil the minimalist, high tech dash with a grotty old fuel gauge, and I haven't heard anything good about the very expensive Westfield electronic gauge. However, I do have a spare sensor channel on the Aim dash/datalogger. (It comes with 4 configurable sensor channels, I have oil pressure, water temperature and oil temperature connected). But, and a very big but, there are two very sound reasons why you can't connect the fuel sender directly to the Aim dash The first is that the fuel level sensor is a low resistance device, it goes from about 2 ohms empty to 120 ohms full, and the 4.5v regulated sensor supply from the Aim unit doesn't supply enough current to cope without fitting a huge load resistor in series which would render the resolution, and hence accuracy, more-or-less useless. The second problem is that the fuel sender float bobs around all the time with road bumps, cornering, accelerating, braking, etc, so if you could get a signal out of it and into a datalogger it would be all over the place, and relatively useless. Fuel gauges get over this by being hugely damped. You could do it electronically with a capacitor but it would be the size and weight of an oil drum. So, one night, with a mate who's an electronics whiz, and fuelled by a couple of pints of Adnams finest we designed this little box of tricks. The first stage is a voltage stabilizer that takes an ignition feed (12.5 - 14.5v) and fixes it at 12v. This then goes off to the sender unit via a 500 ohm load resistor, so we now have around a 2V range from empty to full, that's enough for decent resolution. This signal, which is still bobbing around all over the place as the float jiggles about now goes back into the electronics box and into a little microprocessor chip that averages the signal over 10 seconds and then outputs a stable voltage back to the Aim dash. This means we now have a stable signal, and an accurate one going to the dash/datalogger unit. Are you with me so far...? But there's more...Next, we calibrate the spare configurable sensor channel on the dash so it ranges from 125 at 2V to 0 at 0V, so the digital display will show something between 125 and 0, full to empty. I've also set the alarm (there's an LED alarm display for each of the sensor channels) to come on below 25. Et voila.....assuming a typical road fuel consumption of 25 mpg and a tank capacity of around 5 gallons I now have a digital display on the Aim dash of miles to empty and a warning when it gets down to 25 miles. Quote Link to comment Share on other sites More sharing options...
Dave Eastwood (Gadgetman) - Club Chairman Posted July 18, 2012 Share Posted July 18, 2012 Cool, just curious though, can you not apply the filtering over time or adjust the sample rate to a live analogue input on the Aim dash? Or did you just decide to centralise all the processing in the one outboard box for simplicity? Quote Link to comment Share on other sites More sharing options...
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