=jon= Posted October 30, 2015 Share Posted October 30, 2015 Hi All, For those of you running MS / MJ with switchable maps for LPG, is it possible to post your petrol maps along with your LPG maps please, for comparison, along with the specs of your engine? I've found a load of LPG maps posted before, but not in comparison with the petrol map to show what the delta is between the two... It'd be a useful resource for the future - if anything the offsets are more useful than the raw tables as they can more easily be adapted to other setups... Doing a lot of googling suggests that LPG should be more advanced than the petrol map up to a point, and then retarded compared to at higher RPMs, eg: http://www.acl.com.au/web/acl00056.nsf/0/359683e8a538a3e64a2566c0007bb33e?OpenDocument At the moment mine is set at +10 degrees for LPG across the board, which suggests it may not be set 'optimally'... Thanks Jon 1 Quote Link to comment Share on other sites More sharing options...
zoltan Posted October 30, 2015 Share Posted October 30, 2015 Attachment didn't load 110V8GasAugustMap.msq Quote Link to comment Share on other sites More sharing options...
zoltan Posted October 30, 2015 Share Posted October 30, 2015 You're welcome to have a look at the map I've had in my 110 for the last 5 years. It probably could do with a bit of polishing and tickling but it runs nicely on gas. On petrol it can be a bit chuggy on petrol at low speeds but since it spends it's life on gas I haven't bothered with changing it Engine-wise it's on a 3.5 EFi RV8 with a BLOS carb Quote Link to comment Share on other sites More sharing options...
=jon= Posted October 31, 2015 Author Share Posted October 31, 2015 Hi, It seems to have attached OK - let me check I can open it... Thanks Jon Quote Link to comment Share on other sites More sharing options...
=jon= Posted November 10, 2015 Author Share Posted November 10, 2015 Sorry for the delay, been busy with work... Yours: Mine: Interesting to see the difference - yours isn't that different on the petrol side of things, but mine is a lot, lot more advanced on LPG - just +10degrees across the board. I've not heard it knocking, but it's pretty noisy. It's also been running as is (apart from some minor intake changes by me) for many thousands of miles... It'd be interesting to know where the basemap came from - and if someone with 'tuned ears' and mapping experience could tweak the basemap for more power if it's fairly safe and retarded as supplied... I asked someone that I've used for remapping other cars but he wasn't interested in touching something with LPG... Quote Link to comment Share on other sites More sharing options...
HoSS Posted November 10, 2015 Share Posted November 10, 2015 I think the +10 vs petrol came from Tinleytech, you could ask them. My basemap, ah thats a long time ago, i think it came from someone on here... Quote Link to comment Share on other sites More sharing options...
=jon= Posted November 10, 2015 Author Share Posted November 10, 2015 Thanks Paul.. I did some googling and found the curve suggesting that it should be more advanced low down and less further up... I'll drop Tinley a mail - they just sold me a BLOS carb for the old girl and were very helpful regarding that, will see what they say.. Quote Link to comment Share on other sites More sharing options...
=jon= Posted November 18, 2015 Author Share Posted November 18, 2015 Sorry for the lack of updates, work has been busy recently... I asked Tinley - they said they don't have much experience of MS with LPG, but suggested something along the lines of: Hopefully I can get some time to have a look at see how it runs with a map similar to the above compared... Quote Link to comment Share on other sites More sharing options...
elbekko Posted November 19, 2015 Share Posted November 19, 2015 Fairly similar to what was in your original document then Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 2, 2015 Author Share Posted December 2, 2015 Did some more tinkering over the weekend - with the advance curves as above the LPG map is very similar to Zoltans. If anything his is a few degrees more advanced at higher revs... Also got the BLOS carb fitted. Managed to get it setup, ish - at idle it's still very weak (AFRs of 17-18 or so), and it's lean at cruise, but flat out it richens up to low 14's, high 13's. The BLOS is at the limit of it's adjustment though. Am I right in thinking that I can richen up the idle via the adjustments on the vaporiser, and the overall mixture via the valve in line with the gas pipe? My thinking is that as there's a set of adjusters on the BLOS which weren't there before on the cooker ring, I can add more gas flow at the vaporiser end, and limit it back at the BLOS end... Anyone know control which is which on a Bigas M84? I think the idle screw is the smaller one at the back, and the larger screw shouldn't be touched (diaphragm pressure?), but I can't find any decent instructions anywhere... Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 2, 2015 Share Posted December 2, 2015 You shouldn't have a 'power valve' if using a BLOS, just take it straight out the vapouriser, connect to BLOS. Yes, you turn the vapouriser up if you have reached the limit of the BLOS, there may be one or two screws, one is idle, and bleeds a fixed amount of gas through, the other tensions a spring against a diaphragm which lets more gas through the greater the vacuum. With an OMVL R90e, and a BLOS, on a 3.9, I found I could have the idle screw shut, and the main screw almost fully out (more gas). Then get the running mixture right (3000rpm), and then tweak the idle screw on the BLOS to get the idle mixture right, then check the running, cycle through that a couple of times and you will get it right in short order (20 mins?) especially if you have a wideband. Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 3, 2015 Author Share Posted December 3, 2015 Perfect - thanks for that... There's two screws on the vaporiser, one appears to be idle, the other appears to be the main tension. There's a closed loop controller fitted which also has a stepper in the main gas pipe, along with a manual adjustment valve... When you set it up initially at 3000rpm - was that under no load, or driving? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 3, 2015 Share Posted December 3, 2015 Yep, no load, same as if using a cooker ring. I doubt you will want the stepper in there.... Perhaps once tuned, but it could still hinder the BLOS operation.... Quote Link to comment Share on other sites More sharing options...
HoSS Posted December 3, 2015 Share Posted December 3, 2015 I can add more gas flow at the vaporiser end, and limit it back at the BLOS end... Anyone know control which is which on a Bigas M84? I think the idle screw is the smaller one at the back, and the larger screw shouldn't be touched (diaphragm pressure?), but I can't find any decent instructions anywhere... That sounds sensible. You should have the Bigas manual and the Tinley setup instructions in the paperwork i gave you. Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 3, 2015 Author Share Posted December 3, 2015 That sounds sensible. You should have the Bigas manual and the Tinley setup instructions in the paperwork i gave you. I found a few bits and pieces relating to the LPG but no bigas manual - I did look Bowie - Tinley said that the closed loop stepper would work OK with the BLOS, so it should be OK once it's set up - and to get the stepper to fully open then disconnect it while tuning.. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 3, 2015 Share Posted December 3, 2015 Yep, was about to say, it can work (even says in the instructions IIRC), as you rightly say, for tuning you will want it out Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 6, 2015 Author Share Posted December 6, 2015 Had another fiddle today - wound the manual 'power valve' all the way out. Disconnected the stepper when it was under lean condition (ie. fully open). I still can't get it to idle with a decent mixture - according the wideband it's at about 19:1. It ticks over fine, but obv isn't right. Under load it's fine - cruise it's at about 15:1 which is somewhere close (stoich on gas is 15.7 I think), under hard acceleration it's in the 14's. Will have another play with the main gas pressure next time - the idle pressure screw didn't seem to make any difference when I was playing All a bit trial and error really - I did manage to get it to properly backfire and blow half of the pipework off earlier! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 6, 2015 Share Posted December 6, 2015 How far in the exhaust have you got the wideband? Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 7, 2015 Author Share Posted December 7, 2015 Wideband is about under the front passenger seatbox, along with the closed loop controller sensor. It's probably me just not adjusting the gas pressure enough - did some more research last night online so will have another play when I get a chance... Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 7, 2015 Share Posted December 7, 2015 AH OK, won't be that then, I had issues once with it not far enough in the tail pipe, was obviously getting some pulses of fresh air coming back in, sounds like your set up is a little less doo-hickey than mine Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 7, 2015 Author Share Posted December 7, 2015 My brake servo started hissing ominously on the journey to the station this morning - so I have a feeling there is a vac leak there that's chucking the idle mixture way off.... :-( 1 Quote Link to comment Share on other sites More sharing options...
=jon= Posted December 14, 2015 Author Share Posted December 14, 2015 Swapped the brake servo over the weekend - mixture is now spot on at about 15.2 at idle However swapping from petrol to LPG just after setting off to work this morning resulted in a very loud bang and blowing the IAC valve hose off... Not sure why as it was switching over fine before, and switched over fine again later! Quote Link to comment Share on other sites More sharing options...
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