mikec Posted December 3, 2013 Author Share Posted December 3, 2013 Now ill probably get blasted for this, but I was just messing with the laptop, and thought I'd use autotune to see what that did, that came up with the following map, and I got the idle pretty much on 850 or so. Quote Link to comment Share on other sites More sharing options...
mikec Posted December 3, 2013 Author Share Posted December 3, 2013 Idle us too low wants to be 825-near 900 minimum befire friggin about.... Nige, I've edited the post above, but I did get revs up but they were a little too high and wouldn't come down below about 920rpm Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 3, 2013 Share Posted December 3, 2013 If it's steady, don't mess with it Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted December 4, 2013 Share Posted December 4, 2013 Auto-tune is not really any good at tuning for idle, as it usually ends up lean, but the fact it's richened your idle spot up a fair bit might be an indication that your map was somehow too lean. RV8's like to idle rich, narrowband lambda will be indicating well rich on my 4.6 at idle. Going lean does make the idle come up, that's why it's helpful to have a slight lean slope towards the bottom corner of the map as it stabilises the idle - if the idle drops, it goes a bit lean, which makes the idle come back up. Too much slope and it will hunt round in circles. Are you using a standard fuel pressure regulator & is it connected up correctly, including the vacuum line? Quote Link to comment Share on other sites More sharing options...
Chazza Posted December 4, 2013 Share Posted December 4, 2013 I was just thinking as all this is being tried stationary having the smaller fan might help it warm up a bit. Fridge is correct; the fan has no part in it running cool. The fan is there to cool a hot engine, not chill a cool one - forget the fan and check your thermostat and plumbing, Cheers Charlie Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted December 4, 2013 Share Posted December 4, 2013 Looks like you are slowly getting there now Mike. Tuning MS for your engine and to your liking is never going to be a quick process ……………. for instance, when you get going on the cold start settings you only realistically get one shot at it a day. The fact that the idle came up considerably when you increased the idle fuelling points to the fact that it was indeed running lean. If the idle is too high when you are happy that it is fairly stable and sounds rhythmical then either close the plenum air bleed screw a little, or reduce the idle timing to bring the idle down to your liking, but remember with your cam I wouldn’t let it idle much below 800 rpm With regard to the flat spot ………………… this is most likely to be tied up with the acceleration enrichments. In MS you can set how much extra fuel you want depending on how fast you punch the go pedal. It takes a little time to get it right. I guess next on your list will be getting the cold start enrichment settings correct so that it starts on the button regardless of ambient temperature. Yes …….. change the stat for something hotter ………… either an 82 or 88. Running an engine cool and not letting the oil get up to working temp (80C) will cause engine wear in the long term. Quote Link to comment Share on other sites More sharing options...
ANTOINE Posted December 4, 2013 Share Posted December 4, 2013 I have a 74°c (calorstat in french ) for info, but I live in France, but my region is not very hot, today - 4 ° celsius .......if it can help for the problem Quote Link to comment Share on other sites More sharing options...
mikec Posted December 6, 2013 Author Share Posted December 6, 2013 Ok put Niges new map in today. Idle was very low again, hunted badly again. So I adjusted the idle screw to get it up again, a pic below to show just how far out it was, I daren't unscrew it any more than that Flatspot was unchanged compared to before. Couple of dalatlogs to follow, cheers mike. Quote Link to comment Share on other sites More sharing options...
mikec Posted December 6, 2013 Author Share Posted December 6, 2013 Forgot the pic Quote Link to comment Share on other sites More sharing options...
mikec Posted December 6, 2013 Author Share Posted December 6, 2013 datalogs mctestidle2.xls mctestflatspot.xls Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted December 6, 2013 Share Posted December 6, 2013 Ok put Niges new map in today. Idle was very low again, hunted badly again. So I adjusted the idle screw to get it up again, a pic below to show just how far out it was, I daren't unscrew it any more than that Flatspot was unchanged compared to before. Couple of dalatlogs to follow, cheers mike. You have just taken a step backwards ! All the idle screw does is let in more air ................ it has already been shown that you need more fuel to richen up the idle fuelling. Go into the VE table and increase the fuel in the idle cell and surrounding cells as per my previous post. Once you have a good stable idle it will probably be too fast, so screw in the air bleed screw about halfway in (or so) ..... if it is still troo fast then reduce the timing at idle from 10BTDC to 8BTDC (or lower). To get rid of the flat spot you first need to fine tune the engine with a few data logging runs and then set up the accelation enrichments which will take a while to get right. The map that Nige supplies is ONLY A STARTING point to get the engine running, however, most engines will be slightly different and have different parameter requirements to get them running properly. Quote Link to comment Share on other sites More sharing options...
mikec Posted December 6, 2013 Author Share Posted December 6, 2013 You have just taken a step backwards ! All the idle screw does is let in more air ................ it has already been shown that you need more fuel to richen up the idle fuelling. Go into the VE table and increase the fuel in the idle cell and surrounding cells as per my previous post. Once you have a good stable idle it will probably be too fast, so screw in the air bleed screw about halfway in (or so) ..... if it is still troo fast then reduce the timing at idle from 10BTDC to 8BTDC (or lower). To get rid of the flat spot you first need to fine tune the engine with a few data logging runs and then set up the accelation enrichments which will take a while to get right. The map that Nige supplies is ONLY A STARTING point to get the engine running, however, most engines will be slightly different and have different parameter requirements to get them running properly. Nige sent me a third map this week which I presume had something changed in it to try something else, presumably Nige had an idea. Sure he'll be along at some point to fill us in Quote Link to comment Share on other sites More sharing options...
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