Tony240ZT Posted May 16, 2002 Share Posted May 16, 2002 Anyone ever heard of someone writing a program on a personal computer, like for a laptop that read/modify fuel maps? I'm a programmer, haven't messed very much with serial ports, or parallel ports, but I think it could be done, if the parellel port and processing was fast enough. Any other programmers here that might be able to help in this idea? I do know that the ports on the PC use +5V or 0V as on and off signals, a coil igniter could be used to quickly turn that low amperage +5V into a higher amperage +12V. With the amount of money people spend on stand alone engine management hardware they could afford a pretty good laptop that is much more versitile (mobile multi media to name one nice feature). It would be awesome if all we needed was a wiring harness, a couple sensors, and a commen PC laptop + software to run/tune our cars. Anyone here think there is a better/faster port like USB that could be a better interface for communication? Quote Link to comment Share on other sites More sharing options...
Tony240ZT Posted May 16, 2002 Author Share Posted May 16, 2002 The joystick port is capable of reading 4 potentia meters 0-5V, which could be used for reading the head temp, AFM, O2, and air temp analog sensors. It converts the voltage into pulses (using a multi-vibrator ) that can be converted into a digital resistance number. It also has 4 digital inputs and one could be used for the crank trigger input. The joystick port does not have out put capabilities so a serial port could be used to fire ignition, and injectors. If something like this were possible then multi coil packs could be used. Can anyone foresee synchronization problems? It's not like you have to wait for a device on the receiving end of the serial device to accept the signal. The injectors or the coil igniter would simply switch immediately. Keeping the program real time would have to be the key, using multi threading. Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted May 16, 2002 Share Posted May 16, 2002 Some things to consider.. First, it sounds like you're trying to "trick" the stock ECU. In doing so you're going to be modifying inputs modifying programming you can only guess about. Pitfalls await If you're going to try and run the whole injections system from say a laptop I think you'll find that most OS have too much overhead to be able to effectively do so. Ever have an MP3 stutter because of something else you've done? Expect much worse trying to do this with a laptop. BSOD will take on a whole new meaning! I beleive you'll find dedicated hardware to be more reliable. Go find the DIY-EFI mailing list and read up on their efforts. Youll find some cost savings there if that's your biggest issue. Modifying older GM ECUs is also VERY possible... Go look at the new AEM PnP computers. I've got one in my Supra and it's being heavily talked about on SupraForums. It cost $1200 and is VERY capable once you figure it all out A race unit that will fit anything will be released eventually and I may run one in my Z. P.S. If anyone is interested in FJO Wide Band O2s for tuning give me a shout, I may have a line on them for about 18% under their list - supposedly dealer cost although I'm trying to verify that Will be able to read A/F realtime with less hassle than assembling the DIY WB system, assembled DIY units are on a 3week backorder currently FYI Quote Link to comment Share on other sites More sharing options...
Tony240ZT Posted May 16, 2002 Author Share Posted May 16, 2002 DIY_EFI and EFI332 sound very interesting. I've done some programming with Motorola 8 bit processors before. The EFI332 system is based on a Motorola 32 bit processor. Might be worth learning. I was thinking that an OS like Linux that has far less over head could be pretty reliable. You can also give very high prioity to any jobs you'd like. Well, I may wire up my computer to read in the inputs, just use it for data logging. I think others could find this useful. As for the AEM product, you should know I'm running an AEM Wolf3D under the hood of my `72 240Z with 7M-GTE. Still needs tuning, and the engine needs a drive line. I spent $1500 total (shipped + taxes) for a harness, temp sensors, control unit, hand held LCD display/programmer, PC cables, modified cam possition sensor. If I had another $1500 to dump into my `73 L24ET then I'd go with the Wolf3D system again. I could just buy another harness/sensors for $200 and swap the control unit, has memory moduls to make this easy to do, but that would make the car hard to sell if I ever wanted to Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted May 17, 2002 Share Posted May 17, 2002 That's not the AEM i'm running... This is a brand new one and it damn near knocks the socks off of a Motec system. A bit complicated but I have no doubt it'll run like a raped ape once sorted out. Am looking forward to the Automapping upgrade and eventually traction control - that will be VERY sweet Dual knock sensors, can run 10 injectors, 5 coils, log 4EGT, and on and on. Read abut it on SupraForums.com in the MKIV Tech section. I've got lots to learn abouot it but I'm getting there. FMIC installed today too - it's HUGE. Quote Link to comment Share on other sites More sharing options...
Tony240ZT Posted May 17, 2002 Author Share Posted May 17, 2002 The systems are similar, Wolf has been around for a little while longer in Austrailia. v4.0 came out about the same time AEM made the PnP run one that uses stock sensors. Were you able to rid of your mass air flow meter in doing the ecu swap? I'd hope so. I know the system is suppose to work with the stock sensors, but who wants a mass air flow sensor when it's not necessary and kinda restictive. I'd like to see pics of the intercooler. When are you going single turbo t04R? Quote Link to comment Share on other sites More sharing options...
Bernardd Posted May 17, 2002 Share Posted May 17, 2002 Realtime emulators are only around 150-200 bucks. Connect one to your fancy laptop and voila, you're tuning on the fly. GM guys are using them successfully. Perhaps because their ecu's are mid eighty's and somewhat slower than the new stuff. I would be happy with software that would give me realtime trace to tell me where the ecu is going. I still haven't figured out how the ecu calculates the base pulsewidth at idle. Perhaps this is the hardware changes that JWT (damn them) makes. Personally, I'd go with a buick gn ecu before spending big bucks on a standalone. I can be setup with the entire sensors, harness, maf,etc for around 300 canadian. They are completely hacked with everything there. Boost control, sequential injection, DIS...... Other than datalogging, which really is nice, there is no benefit to spraying a lot of cash on these standalone units.(IMHO) I lucked into a megasquirt so that'll do nicely for me. I don't need to have ignition control as I already have the 450hp ignition maps installed in my 300zxt ecu. Tony, have you done anything with the motorola 6802 in the 300zxt? Maybe you can help me out with my quest. Bernardd Quote Link to comment Share on other sites More sharing options...
Guest jens Posted May 17, 2002 Share Posted May 17, 2002 Try and ask here http://groups.yahoo.com/group/megasquirt/ And see that bruce bowling has made http://www.bgsoflex.com/megasquirt.html Quote Link to comment Share on other sites More sharing options...
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