charlie_pank Posted April 11, 2005 Share Posted April 11, 2005 I spent this weekend rigging up Lawrence's WB O2 sensor to my Emerald, so I'm now able to log the AFR as I trundle along. The results are pretty good as I seem to be almost spot on throughout the map (bit rich at low revs/throttle and a bit lean at high ones) but nothing major. Once the engine's up above 50DegC it idles superbly, but just after startup it's all over the place, in fact I have to hold it at about 2500 rpm on the throttle otherwise it stalls. The AFR while this is going on is about 13, but I think there's a lot of unburned fuel around as it reeks of petrol while it's starting up. My plan to address these issues is to leave the base fuel map alone (as it idles fine when warm). Looking at the logging output when it's idling happily it seems to sit around 1000 rpm with 18 degrees of advance, so I'm going to put that in as the value at 1000 rpm tp, 0. then reduce it a bit for 1500 and a bit more for 2000. The end result timing map will look like this for TP:0 : 0 500 1000 1500 2000 20 19 18 13 8 I don't have an IACV and I'm going to switch off the idle control on advance for the moment til I can get this sorted - I'm assuming if I ramp up the advance enough around 0 - 1000rpm I should be able to achieve the same effect as the idle control. Can anyone give me any tips about what AFR I'm looking for during warmup? Can anyone offer me any advice about whether my approach is the right one - should I be concentrating on the coolant enrichment map instead (I'm taking some fuel out of that to try and bring the AFR to 14 when the coolant temp is low)? Thanks C Edited by - charlie_pank on 11 Apr 2005 14:31:54 Link to comment Share on other sites More sharing options...
Myles Posted April 11, 2005 Share Posted April 11, 2005 I'd like to know how to tweak cold-starting in the Emerald as well - not so much idle, but getting it to catch quicker... Project Scope-Creep is underway... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
charlie_pank Posted April 11, 2005 Author Share Posted April 11, 2005 Damn! Thought I was going to have got an answer to my questions then!! Link to comment Share on other sites More sharing options...
Johnty Lyons Posted April 11, 2005 Share Posted April 11, 2005 Hard luck Charlie we all want that answer so soon as you get it let us all know *wink* Link to comment Share on other sites More sharing options...
charlie_pank Posted April 11, 2005 Author Share Posted April 11, 2005 Grrrrr! 😬 I had a great response to mapping questions over the weekend on the se7ens list, but can't access email from work so I'll have to wait til I get home... Edited by - charlie_pank on 11 Apr 2005 15:39:36 Link to comment Share on other sites More sharing options...
Mike Bees Posted April 11, 2005 Share Posted April 11, 2005 You may not get a very sensible reading from the lambda during warm-up since it may not be fully up to temperature. A couple of tips: If you don't have an IACV then you may need to set your throttle stop to give a fairly fast warm idle in order to get it to idle cold. A cold engine needs to make more power to turn it over at a given rpm compared to when it's warm (more friction/thicker oil etc.), so it needs more air & fuel when it's cold then when it's warm (this is where the IACV comes in useful). To play with the fuelling, just tap the fuel map up & down (+/- keys) to see if it runs faster as you add/remove fuel, then stop the engine, go to the cooland correction fuel map and change the % enrichment appropriately. Repeat. You'll need to repeat this process a few times from fully cold to get it roughly right. You're right to do with with the idle advance correction disabled. However it will make your life a bit easier if you add some advance to the coolant correction ignition map. Mike Link to comment Share on other sites More sharing options...
charlie_pank Posted April 11, 2005 Author Share Posted April 11, 2005 Cheers Mike. I'm fairly sure that my problems are related to air/fuel because all was fine before I fixed the air-leak. The WB O2 sensor I'm running has a heater in it and a little light comes on on the box when it's up to temp, so I know it's reading correctly before I start cranking. I really hope I don't have to adjust the idle screw as then I'll have to reset where 0 is on the throttle pot then I'll have to shift all the maps appropriately which would be a REAL pain! At the moment it won't run at all at TP:0 when it's just started, so adjusting the fuel to get it working with the trim is going to be tricky - but I see what you mean. Edited by - charlie_pank on 11 Apr 2005 15:57:17 Link to comment Share on other sites More sharing options...
Mike Bees Posted April 11, 2005 Share Posted April 11, 2005 Changing the idle position won't affect the maps, it'll just put you in a slightly different place in the map at idle (slightly further away from load site zero). Also the amount of throttle movement required to get a whole heap more air at idle is really tiny, it'll actually only move you a few percent along the journey between load site zero and load site one. Mike Link to comment Share on other sites More sharing options...
Myles Posted April 11, 2005 Share Posted April 11, 2005 I'll have to reset where 0 is on the throttle pot then I'll have to shift all the maps appropriately which would be a REAL pain! Eh? You just re-run the TPS setup routine immediately after the adjustment... Takes about 20 secs. A cold engine needs to make more power to turn it over at a given rpm compared to when it's warm (more friction/thicker oil etc.) You're telling me! I started my engine on Sat to get to the MOT (the car lives outside and OT was at 2deg above freezing) - it started, idled badly for a few secs and then conked-out. Had to give it a tiny bit of assistance with the throttle to get it through this phase. Project Scope-Creep is underway... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Edited by - Myles on 11 Apr 2005 17:02:14 Link to comment Share on other sites More sharing options...
Lawrence_Z Posted April 11, 2005 Share Posted April 11, 2005 AS Mike has said for good idle control you need air. It's necessary to have the car racing at idle without the idle control operational, as the idle control is better at cutting revs than adding them. This makes for easier starting too. Lawrence Link to comment Share on other sites More sharing options...
Strangely Posted April 11, 2005 Share Posted April 11, 2005 Hi Charlie, I can only echo what others have said about adjusting the TBs to give enough air at idle. I struggled with having to feather the throttle when starting the engine for about a year, and tried all sorts of mucking about with the map. Eventually I admitted defeat, and tweeked the throttle stop so that it is now slightly more open. I did this scientifically by running the Emerald software in live mode and watching the throttle pot reading as I feathered the throttle to keep the engine running. Then I stopped the engine, and with the live view still active (requires the ignition to be on) I adjusted the throttle stop to give that opening (the retrained the Emerald). It was only about 5 more than before, but it made the world of difference. Now I don't need to touch the throttle at all to start the car, and it's only slightly over 1000 rpm idle even when warm. I also noticed that the advance was far too high at idle, which was making the revs try to race higher. I ended up with 10 at 500 rpm, 2 at 1000, 0 at 1500, 10 at 2000 (all at load site 0), with startup advance of 5 deg. Let me know if you'd like me to send you my map. It almost certainly won't be right for your engine, but you can compare to see which areas differ markedly. Good luck. Having a turn-key engine is such a luxury . Link to comment Share on other sites More sharing options...
Strangely Posted April 11, 2005 Share Posted April 11, 2005 Myles, I think my engine got easier to turn over when I reduced the advance at 500 rpm / load site 0 from 20 to 10 deg. With all of the temperature compensations added in, it was using some HUGE amount of advance. If you'd like to see my map then let me know. It's been starting fine in all of the cold weather, and on the odd warm day we've had recently. I'll have to wait to find out if it needs further tweeking for the scorchers . Link to comment Share on other sites More sharing options...
Myles Posted April 11, 2005 Share Posted April 11, 2005 Hmm, well if I'm reading my map correctly, at load-site 0, I've got 10,20,5,5,15,30 and then 45 all the way up in the ignition map. Startup-timing is set to 5 degrees advance. Temp correction gives 8 deg advance at 0 deg C dropping to 0 deg advance at 50 deg C. How does this sound? I notice that Roy Booths map (or one of them) on which mine was based has massively less advance in the ignition map for load-site zero - but then I also remember DW saying something in my basemap was just plain wrong at low throttle openings - the engine kept stalling coming into junctions. Project Scope-Creep is underway... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
charlie_pank Posted April 11, 2005 Author Share Posted April 11, 2005 Well I ended up flattening the battery trying to start the f*cker today! I was determined not to touch the throttle to do it and played around with all the maps I could. Ended up opening the idle screw just a touch and it (of course) made all the difference (Once I'd sent Helen out in the shopping car to buy some jump leads). So I reset the 0 position for the throttle and I'll have to wait til tomorrow to try again for 10 Deg C. I'm pleased that I've got the idle steady without the idle control stuff in place, I might try reducing the advance a bit at TP: 0, 500 rpm if I can get it starting and idling ok. If I can get it giving a rock solid idle without the idle advance control is there any reason I should use it? Link to comment Share on other sites More sharing options...
Strangely Posted April 11, 2005 Share Posted April 11, 2005 I turned on idle control with advance (after tweeking everything with it turned off), based upon this reasoning. If the idle is stable where I want it, or is even running a little fast, then the ECU won't do anything extra. However, if the revs start to drop, then I'd rather the ECU kick in with a little extra advance than have the engine stall. Link to comment Share on other sites More sharing options...
Strangely Posted April 11, 2005 Share Posted April 11, 2005 Myles, at load site 0, my ignition advance goes: 0: 5 500: 10 (high to kick the revs up if they drop below 1000) 1000: 2 (this is where it wants to sit) 1500: 0 (low to make the revs drop if the idle is too fast) 2000: 10 2500: 10 3000: 5 My coolant enrichment for ignition is: -10: 10 0: 7 10: 8 20: 5 30: 3 40: 2 50-100: 0 110: -2 120: -5 Air temp correction: -10: 3 0: 2 10: 1 20-40: 0 50: -1 60: -4 70: -7 80-120: -10 Link to comment Share on other sites More sharing options...
charlie_pank Posted April 12, 2005 Author Share Posted April 12, 2005 Strangely, your ign timing is WAY different to mine. I'm running with 18 degrees idling at 1000 rpm. What's your engine & setup? I put in 18 degrees because that's where it 'wanted' to idle when I had the idle correction in. I've currently got that switched off. Adding up all the different maps for coolant temp, air temp etc... what is the final figure in the live adjustments screen when you're idling at 1000? Link to comment Share on other sites More sharing options...
Strangely Posted April 12, 2005 Share Posted April 12, 2005 My engine is a 1.8K with Lotus Sport 135 head, 644 cams (I think), Jenvey DTH TBs, Bernard Scouse airbox, Powerspeed 4:2:1 exhaust. I'll try to check my actual idle advance later today (in the office now ☹️). Link to comment Share on other sites More sharing options...
oilyhands Posted April 12, 2005 Share Posted April 12, 2005 The secret to a good hot idle and good cold one is i) make sure the engine is getting enough air, this is correct when the engine idles at 1000RPM with zero advance *with the idle control turned off* with the engine hot. ii) make sure speed site 1000 has 0 degrees of advance and that idle control is turned on iii) make sure the IACV settings are null and switched off iv) use these settings for coolant temp corrections Ign 10 7 8 5 3 2 0..... inj 55 50 45 35 18 11 4 1 0..... str 85 75 70 65 58 45 30 18 12 12........ v) make sure the throttle pot is aligned and the TBs balanced Make sure you are drawing sufficient air!!, around 4-5CFM on each barrel is correct. Any more than this and you will soar when hot, less and you will struggle when cold. Oily Edited by - oilyhands on 12 Apr 2005 11:00:21 Link to comment Share on other sites More sharing options...
charlie_pank Posted April 12, 2005 Author Share Posted April 12, 2005 Now there's some useful info - cheers oily - I'll go back and adjust the airflow so I can run a hot idle at 0adv and work from there. That's fantastic - I just needed 1 reference point - now I've got it *wink* [1.6k with std ally plenum and 4-2-1 exhaust] Edited by - charlie_pank on 12 Apr 2005 11:05:12 Link to comment Share on other sites More sharing options...
charlie_pank Posted April 13, 2005 Author Share Posted April 13, 2005 Right, getting on well with injection mapping. And I've got the idle sorted out in terms of advance and throttle stop. I'm a bit concerned that my advance is quite high in some areas of the map - eg. 6000 rpm TP4 = 40 Degrees 4500 rpm TP6 = 27 Degrees Does this look reasonable? Is there a base map I can use for everything except idle (which is sorted)? - It's a 1.6k with standard cams and the standard (big) ally plenum. Edited by - charlie_pank on 13 Apr 2005 09:36:16 Link to comment Share on other sites More sharing options...
charlie_pank Posted April 13, 2005 Author Share Posted April 13, 2005 Also - how on earth do you map ignition? What are you looking for to tell you whether to advance or retard? Link to comment Share on other sites More sharing options...
oilyhands Posted April 13, 2005 Share Posted April 13, 2005 The more the cylinder fills, the less the advance needed, The more the RPM the more advance is needed, therefore on full throttle you need relatively little advance (from 10 degrees at 1000RPM, ramping to 28-30 at 4000), as the throttle position lessens then you need more advance. See my EMS article or ignition timing article at http://members.aol.com/DVAndrews, either will help you to understand the prionciples. 40 degrees at part throttle is not unusual as long as it is past 3500. Oily Link to comment Share on other sites More sharing options...
charlie_pank Posted April 13, 2005 Author Share Posted April 13, 2005 Cheers oily, I've just been reading it actually :) Reading this I understand the principles of partial filling etc... and why advance is necessary. I also read that the way that the ignition is mapped on a RR is to increase the advance at each site as much as possible without pinking (detonation/pre-ignition). Thing is, I'm not sure I can recognise pinking at WOT, 6000 rpm on the road! Not convinced I'd recognise it when stationary actually, I know it's a pinging sound, but apart from that what makes it stand apart from all the other rattles and bumps a 7 makes? Is it a regular ping (ie the cylinder pings on every compression cycle)? Link to comment Share on other sites More sharing options...
Mike Bees Posted April 14, 2005 Share Posted April 14, 2005 You really shouldn't be trying to map the ignition without a rolling road or dyno. The technique used is to get the engine steady at each load site (rpm/throttle position combination) and then slowly increase the advance until either the power stops increasing or it starts pinking. If it starts pinking then the advance is backed off slightly for that site. Then on to the next site in the map and repeat etc. You really can't do this by driving the car around on the road. Mike Link to comment Share on other sites More sharing options...
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