Paul Booth Posted September 10, 2001 Author Share Posted September 10, 2001 ...and which camp are you in Phil, strange behaviour or 140+ MPH? Quote Link to comment Share on other sites More sharing options...
Phil Wall Posted September 10, 2001 Share Posted September 10, 2001 Last time I took the car out for a fast run, it was pulling like a train at 165, with quite a way to go to the red line:biggrin: Still have not found the limit yet. So I guess that puts me inthe 140+ I do occasional get a lack of kick down but that just might be me! I have followed this thread closely as I think I may change my JIC box to a better one just for reasurance that all is OK. Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 10, 2001 Author Share Posted September 10, 2001 Phil, the JIC box is fine, as far as I know. This is about the Engine ECU+ECT ECU getting conflicting speed data, IMO. If you don't have jerky gearchanges and you obviously don't have a speed restriction I wouldn't worry. Quote Link to comment Share on other sites More sharing options...
Phil Wall Posted September 11, 2001 Share Posted September 11, 2001 My gear changes are fine, I have not noticed any jerks, well not from the gear box:biggrin: Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 11, 2001 Author Share Posted September 11, 2001 I'm betting that I could make this all go away if I fitted an engine ECU & ECT ECU with a later software release. None of the later j-spec cars seem to have this problem after they've been converted, it only seems to be the first models. You know, the "let's ship it and see what bounces back" models. No, sorry, that's Microsoft isn't it. In Toyota's case it's incompetent software engineers, incapable of identifying a bug until it's been shipped and people show them where it is. Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 21, 2001 Author Share Posted September 21, 2001 I'm most impressed with Abbey Toyota in Redhill (it's where JIC get their bits from). My local Toyota couldn' find their arse with both hands, getting me the warning light panel instead of the odo. Abbey did say it would be October before they could get me one but it's just turned up. Fitted it and I'm now feeding my ECU daisy chain with 1:1 speed data. Boy does that gearbox change smoothly now. Tomorrow I fit the dreaded HKS SLD to the Engine ECU, the ECT ECU and the TRC ECU. I'm hoping I've resolved the 120MPH issue by this time tomorrow. If nothing else, I feel happier knowing the gearbox isn't being stressed the same. Here's one for the lateral thinkers amongst you: If my Cruise ECU was being fed with 8:5 speed signal and it's range was about 28MPH to 70MPH, why, when it's being fed with 1:1 speed information, does it *still* operate from 28MPH to 70MPH? Quote Link to comment Share on other sites More sharing options...
Guest Ash Posted September 22, 2001 Share Posted September 22, 2001 Paul, I've always been meaning to ask you what it is you mean by 8/5ths speed signal? You have stated this in other posts and I don't quite understand what you mean. Yours, J Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 22, 2001 Author Share Posted September 22, 2001 KPH-MPH conversion, by changing the data from speed sensor number 1 requires you divide the data by 1.6 (or 8 [km] divided by 5 [miles]), i.e., map the input signal in km to an output signal in miles. Obviously, you can't have 0.6 of a pulse and if you output 1 pulse for every 2 you get in (/2) and then output an extra one on the 8th input pulse, it 'could' cause a tremble in the Speedo needle at low speeds. What I used to do for sensor/instrument mapping, for example on the Jaguar XJ200, was to actually measure the pulse 'width' of the input signal and map that to an output pulse width (assuming an output square wave, of course), i.e., you're converting wavelength rather than frequency. This method is *extremely* accurate at low speeds. More information than you asked for I know, but someone else might be a hobbiest and might want to have some fun. Quote Link to comment Share on other sites More sharing options...
Guest Ash Posted September 22, 2001 Share Posted September 22, 2001 Thanks for the info. Yes agreed regarding measuring the pulse-width gubbins. That's basically the design I had in mind for recalibrating my speedo as the overall circumference of my wheels & tyres are now bigger than stock. I though the easiest (and the best way as it happens) is to simply convert the frequency into a corresponding voltage, scale the voltage as I please, and feed it into a V/F convertor. Ah, I see what you are saying now. Of course, I realise all about dividing the signal from KPH to MPH but it was your specific use of the fraction 8/5ths that I couldn't get to grips with. What you are saying is, the signal that has been *divided* by 8/5ths, not a signal that is 8/5ths of the original... which is how I was reading it. I think that's because, in my mind, I have always thought of the MPH signal as a 5/8ths signal. As regards the Cruise ECU question, for whatever reason the signal being fed to it can not have changed. If you feed the Cruise ECU with a divided signal it *will* work from about 40mph to 120mph. Yours, J Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 22, 2001 Author Share Posted September 22, 2001 Yup! Exactly my fear. It would mean that 'auto-electrician-rock-ape' has been fiddling with the harness where he shouldn't have been. This is what I feared/suspected all along. My nightmare is that he's tried to be clever (oxymoron) and has either tapped sensor no 1 elsewhere or (please God no) he's tapped sensor no 2. I'm doing the SLD today (not touching the RL TC until the SLD works 100%) but when I come to fit the control for the TC I'll check over the harness to the Cruise ECU. Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 22, 2001 Author Share Posted September 22, 2001 Quote: from Ash on 9:44 am on Sep. 22, 2001[br] I though the easiest (and the best way as it happens) is to simply convert the frequency into a corresponding voltage, scale the voltage as I please, and feed it into a V/F convertor. Yours, J BTW, while it's common knowledge of my love of playing with the PIC chip, there used to be an 8051 derivative which is far better suited to this type of work. I think the 'external ROM' part number is 83C552 and I think the programmable device is 87C552. It's totally fabulous for low res. pulse and analogue signal mapping. It has ADC input ports, DAC output ports, timer ports (clocked or gated by external inputs - perfect for either frequency or width measurements) and PWM outputs. It's a bit expensive for single signal applications and is really better if you need to deal with the whole of the vehicle's sensory data and display (it's what I used on the back of the XJ220 dashboard, nothing else). You *could* measure, convert and display 8 or more different sensory channels. For just dealing with the speed sensor no 1 data, the PIC chips are the most cost effective, ask Mr Betts. Incidentally, his new improved KPH/MPH convertor is working now, complete with 8:5 *AND* a 1:1 outputs for those people who want their gearchange and PPS to behave correctly. He's also looking at proving a simple SLD function by capping the sensor no 1 frequency which works x1,000,000 better than the manner it's done by everyone else; the argument being, by the time you hit the 112 barrier, you're in top anyway so why bother with HKS solenoid interference. It seems to be working fine on his car. Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 22, 2001 Author Share Posted September 22, 2001 Oh bugger! my wheels need balancing for speeds in excess of 130 MPH.... YEEEESSSSSSS! So *that's* why HKS intercept Solenoid 2..... (Bwuhahahaaaaaa!) HKS rule! Now for the RL TC. I think this thread is now dead. Yeehaaaaaaa!. Oh yeah! almost forgot. Rock-ape had been cutting into the harness around the Engine ECU speed circuit too. Now I *know* I'm going to find his footprints around the cruise ECU. Quote Link to comment Share on other sites More sharing options...
Guest Ash Posted September 22, 2001 Share Posted September 22, 2001 I take it then your 120 mph limit has been exceeded by a mile and a half? Yours, J Quote Link to comment Share on other sites More sharing options...
Paul Booth Posted September 22, 2001 Author Share Posted September 22, 2001 Bottled out at 140 'cos the rear wheel vibration was getting too much for my mechanical sensitivity to bear. It wasn't pulling like a train at that speed, but it *was*pulling. A big difference was the re-mapped gear timings and consequent power spread, but I'll say no more on that as Pete wants to leverage that and I would like someone other than HKS (who sell a product into the UK and can't produce an English manual) get some benefit. Quote Link to comment Share on other sites More sharing options...
Guest elegantparts Posted March 16, 2007 Share Posted March 16, 2007 Hi there Does any one know where and what colour is the speed signal wire on a 1999 none turbo supra.......PLEASE I NEED TO WIRE A FOUR WIRED CONVERTER FOR ESVA. MANY THANKS DAVID Quote Link to comment Share on other sites More sharing options...
Jake Posted March 16, 2007 Share Posted March 16, 2007 Holy crap! It's a new thread resurrection record! Quote Link to comment Share on other sites More sharing options...
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