geoffbeaumont Posted March 29, 2006 Share Posted March 29, 2006 Half way through installing the Megasquirt'n'EDIS in the truck - hopefully get it all up and running this weekend (yeah...right... ). So... does anyone have any maps and/or sensor definitions to get me started? I'm running a standard 3.5 RV8 (hotwire flavour), all the sensors are standard OEM ones barring the air temperature sensor, which I think is the 'default' Megasquirt one (a 3K thermistor kindly supplied by Fridgefreezer). Ignition is EDIS 8 and will have separate maps for petrol and LPG. A couple of questions too: Am I right in thinking the idle ignition advance on petrol should be 8deg? EDIS does a minimum advance of 10deg, so I'm thinking it might be worth offsetting the sensor a couple of degrees and adjusting the ignition timing maps accordingly? Will my timing light work okay with EDIS? It's wasted spark so the plugs fire on the exhaust as well as ignition stroke - obviously this will trigger the light twice as often as on a conventional system, but the balance weight timing mark will still be at the same angle for both events, won't it? TIA Quote Link to comment Share on other sites More sharing options...
western Posted March 29, 2006 Share Posted March 29, 2006 Fridge your needed Now never about when his fav subject pops up Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 29, 2006 Share Posted March 29, 2006 Flapper EFI V8 3.5 std advance at tickover is around 6 degress not 8. Other than that POST PICS ! Nige Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted March 29, 2006 Author Share Posted March 29, 2006 Flapper EFI V8 3.5 std advance at tickover is around 6 degress not 8.Other than that POST PICS ! Nige It's a hotwire not a flapper, but I'll double check. Not sure if I've enough leeway to move the sensor that much (could slacken the pulley stack and move the trigger wheel, I guess), and anyway I want to leave the limp home mode (10deg fixed) usable on both petrol and LPG. Will get some pics - probably at the weekend with a decent camera. You've seen most of the interesting bits before, though - apart from the alloy brackets Geoff Greenwood fabricated for me months ago it's just a few bits of Ford and a wiring loom. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 29, 2006 Share Posted March 29, 2006 Hotwire isn't 10 either, bout 6 too, could look it up but its 12.30 and I'm at a meeting at 6.30am Nige Quote Link to comment Share on other sites More sharing options...
Niall_CSK Posted March 30, 2006 Share Posted March 30, 2006 Agree, it varies between 5-8 deg regardless of efi system in my experience, are you keeping the LR injection system and doing just the edis? They will run on petrol at 10 when warm but it's pretty lumpy, can confirm this from messing around with RPi's arse about face retard unit, so if it's for limp home you would expect that the engine is warm already and hopefully most of the time it will be running above 1000 rpm. I am surprised that MS won't go less than 10, not having looked at MS in any depth yet I expected that all to be in lookup tables so -ve value offset would get you less than the 10. Am I making false assumptions here? Quote Link to comment Share on other sites More sharing options...
imspanners Posted March 30, 2006 Share Posted March 30, 2006 How do you know EDIS 8 has a minimum 10 degree advance? I've worked on the EDIS 4 module which can do whatever it's told by the ECU. The EDIS system takes the crank sensor signal and sends it to the ECU as a PIP (Profile Ignition Pickup) value. The ECU then adjusts the timing according to the relevant MAP, and sends a SAW (Spark Advance Word) signal back to the EDIS. This SAW signal is what determines spark timing. The LIMP mode, works in the event of the EDIS module not receiving a SAW signal. So if the PIP wiring is bad or the ECU plays up, it'll still fire the spark, which is set at 10 degrees, (usually midway in the timing advance). HTH Quote Link to comment Share on other sites More sharing options...
jules Posted March 30, 2006 Share Posted March 30, 2006 Fridge or Mr Haynes are the guys I spoke to Dave about Ashley's system failing I did not know that, that system was only a test setup for a mates RR to do one event with and see how he got on Dave never expected Ash to end up with it so going to Ireland and back it didn't do too bad as a bench test unit never designed to leave the work shop. Quote Link to comment Share on other sites More sharing options...
02GF74 Posted March 30, 2006 Share Posted March 30, 2006 Will my timing light work okay with EDIS? It's wasted spark so the plugs fire on the exhaust as well as ignition stroke - obviously this will trigger the light twice as often as on a conventional system, but the balance weight timing mark will still be at the same angle for both events, won't it? Not sure what you mean by "balance weight timing mark". The crank rotates twice for a combustion cycle (4 stroke). The timing marks on the crank pulley are relative to TDC; there are "two TDC's"; one for compression and exhaust strokes. So yes, the strobe will light the timing mark and it will be in the same place; the only difference is that it will be lit once per engine revolution instead of once per two revolutions. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted March 30, 2006 Share Posted March 30, 2006 Stuck with dialup at the moment so I'll be brief. There is a sensor definition somewhere (thermfactor.inc) for the RV8 coolant sensor, try the megasquirt_uk Yahoo! group or the www.msefi.com forum under "success stories". Failing that it's easy enough to make your own file, it's only a list of voltage readings and temperatures. There might even be a little program to make it for you if you have a poke round the MSEFI web page for "EasyTherm". I don't have an ignition map to hand although there are people out there running MS'n'S so you should be able to find someone who can help. I'd suggest e-mailing Dave White (http://www.yorkshireoffroadclub.net/vehicles/bgs/) as a first-off. For fuelling maps, Dan's is as good a starting point as any: www.getmuddy.co.uk click on the MSEFI logo on the right. Jules - correct about Ash's ECU, I fixed it in 5 seconds and it's now in a Hilux with a V8. Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted March 31, 2006 Author Share Posted March 31, 2006 Cheers Fridge. Jon W's supplied me with the ignition map from his 3.5RV8, so that should be a good starting point for mine. Would be nice to get hold of a known good ignition map for LPG, but I can start off by just advancing the whole map a few degrees - will at least be no worse than what I've got now. Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted March 31, 2006 Author Share Posted March 31, 2006 Agree, it varies between 5-8 deg regardless of efi system in my experience, are you keeping the LR injection system and doing just the edis? Nah, in for a dollar... I'm switching over the petrol fueling too. LPG will have to stay under the Landi-Renzo ECU as I have a venturi gas kit. If it was injected I might be able to get Megasquirt running the whole lot They will run on petrol at 10 when warm but it's pretty lumpy, can confirm this from messing around with RPi's arse about face retard unit, so if it's for limp home you would expect that the engine is warm already and hopefully most of the time it will be running above 1000 rpm. They'll run at more than ten on petrol, even cold - I run an idle advance of 12deg with the dizzy. It is indeed a bit lumpy, but as I only run on petrol until it's warm enough to switch to LPG it's worthwhile for the better performance on the latter. I am surprised that MS won't go less than 10, not having looked at MS in any depth yet I expected that all to be in lookup tables so -ve value offset would get you less than the 10. Am I making false assumptions here? How do you know EDIS 8 has a minimum 10 degree advance?I've worked on the EDIS 4 module which can do whatever it's told by the ECU. The EDIS system takes the crank sensor signal and sends it to the ECU as a PIP (Profile Ignition Pickup) value. The ECU then adjusts the timing according to the relevant MAP, and sends a SAW (Spark Advance Word) signal back to the EDIS. This SAW signal is what determines spark timing. The LIMP mode, works in the event of the EDIS module not receiving a SAW signal. So if the PIP wiring is bad or the ECU plays up, it'll still fire the spark, which is set at 10 degrees, (usually midway in the timing advance). I'm working from memory here...definitely time to go reread the docs If EDIS4 will do less than 10deg I'm pretty certain EDIS8 will too - so far as I know their operation is exactly the same. Not sure what you mean by "balance weight timing mark". I mean harmonic damper, of course... The crank rotates twice for a combustion cycle (4 stroke). The timing marks on the crank pulley are relative to TDC; there are "two TDC's"; one for compression and exhaust strokes.So yes, the strobe will light the timing mark and it will be in the same place; the only difference is that it will be lit once per engine revolution instead of once per two revolutions. That's what I thought...just remembered seeing something on a Megasquirt forum post about standard timing lights being no use with wasted spark and starting to think I might have missed something. Probably just someone talking borlocks I'm going to have to work tomorrow now , so no fun for me. Jonathan's looking for something to keep him out of mischief, though, so I'll leave him to finish off the wiring - he'll do a better job of it than me anyway Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted March 31, 2006 Share Posted March 31, 2006 will at least be no worse than what I've got now. It's not until you start tuning that you realise just how large the error margins are in the standard stuff, especially switching from mechnical systems like carbs or dizzies to closed-loop electronical. Don't forget to save your maps when you get it working and BEFORE you start "just fine tuning" the settings Quote Link to comment Share on other sites More sharing options...
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