tomek Posted May 9, 2012 Share Posted May 9, 2012 I finally hooked my LM2 to XX - hey , it has taken only 3 years - and I`d like to speed up proceeding . How lean can you practically go on XX under light load in 2000-5000 rpm range ? I`ve already removed epic amounts of fuel from MP file in 2-20 % cells , now my AFRs in this range somewhat resemble normalcy ( 13-low 14`s ) , but I`d like to know what is a target point without unnecessarily going too lean with all consequences like drivability ,etc . I`m also looking at the info how AAP and MP files overlap each other . If someone has useful info please share , I don`t feel the urge to reinvent the wheel here . Quote Link to comment Share on other sites More sharing options...
cbrxxquad Posted May 9, 2012 Share Posted May 9, 2012 Eric is all that you need to know Quote Link to comment Share on other sites More sharing options...
tomek Posted May 14, 2012 Author Share Posted May 14, 2012 Eric , where are you Eric ? If I ever offended you I sincerely apologize , OK ? I wanna pull this damn thing off the bike and start screwing with my Volvo , looking for extra highway MPGs . Quote Link to comment Share on other sites More sharing options...
HANKSXXX Posted May 14, 2012 Share Posted May 14, 2012 I may not be Eric but I'll offer this after riding around and monitoring an wide band A-F gauge for a couple thousand miles. Slight variations in elevation and temperatures show up as changes in the A-F ratio, Hold a steady speed on level ground and then start to go up a barely perceptible hill and you should see an change. I started looking for trends rather than absolute numbers, however, steady state cruise seemed happiest in the 13.8-14.0 range. A .020" shim under the clip made a relevant difference and showed a 2 mpg change. The caveat here is my bike is carbed.... Any leaner, at stociometric for example, and I felt the bike lost a bit of response. Hope that's at least some help or food for thought... Hank Quote Link to comment Share on other sites More sharing options...
K Viktor Posted May 15, 2012 Share Posted May 15, 2012 AFR at low loads/rpm also depends from intake valves clearance. Smaller clearance = leaner target mixture. Quote Link to comment Share on other sites More sharing options...
jon haney Posted May 15, 2012 Share Posted May 15, 2012 AFR at low loads/rpm also depends from intake valves clearance. Smaller clearance = leaner target mixture. Okay, I give up. What does valve clearance have to do with AFR? And is that piston-to-valve clearance or valve bucket-to-cam clearance? Quote Link to comment Share on other sites More sharing options...
K Viktor Posted May 15, 2012 Share Posted May 15, 2012 AFR at low loads/rpm also depends from intake valves clearance. Smaller clearance = leaner target mixture. Okay, I give up. What does valve clearance have to do with AFR? And is that piston-to-valve clearance or valve bucket-to-cam clearance? Yes, valve to cam clearance. That affect to valve open time and engine volumetric efficiency, as well as changing cam lobe height. Quote Link to comment Share on other sites More sharing options...
jon haney Posted May 16, 2012 Share Posted May 16, 2012 AFR at low loads/rpm also depends from intake valves clearance. Smaller clearance = leaner target mixture. Okay, I give up. What does valve clearance have to do with AFR? And is that piston-to-valve clearance or valve bucket-to-cam clearance? Yes, valve to cam clearance. That affect to valve open time and engine volumetric efficiency, as well as changing cam lobe height. Hmmm, didn't think a few thousandths would make any kind of noticeable difference. Quote Link to comment Share on other sites More sharing options...
tomek Posted May 16, 2012 Author Share Posted May 16, 2012 AFR at low loads/rpm also depends from intake valves clearance. Smaller clearance = leaner target mixture. Okay, I give up. What does valve clearance have to do with AFR? And is that piston-to-valve clearance or valve bucket-to-cam clearance? Well , tighter valves increase cam duration and more importantly overlap so it can effec Yes, valve to cam clearance. That affect to valve open time and engine volumetric efficiency, as well as changing cam lobe height. Hmmm, didn't think a few thousandths would make any kind of noticeable difference. Well , tighter valve clearances increase cam duration and more importantly overlap , so it can effect AFRs , but that does not really effects what I was trying to do here . Anyway , I`m done with this project , I`ve settled for 13.5 - 14.0 under very light load , essentially when you are coming on the throttle from engine braking situation , cruise is in 15.0 -15.5 range and of course afrs go down when WOT . I`d say it is good enough , I could probably got 1-2 more mpg but I need my wideband sensor for other projects . I`ve removed great amounts of fuel in light load / cruise conditions , internet map was insanely rich in this areas . It seems I`m getting extra 15 - 20 miles per tank ( additional 3-4 mpg ) in city driving . Now I gotta do something with those fugly welds done by me on the exhaust pipe . Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 25, 2012 Share Posted May 25, 2012 OH... Hello... Sorry I completely missed this thread, thankfully I got a Email.... I'm awake now. No apologies necessary... we've always been on the same side. It looks like you are on the right path... How lean can you go, depends on the amount of load and rpm. In my experience, (years of running leanER), you can safely do this... Under cruising conditions, very light load, motoring down a road just maintaining speed and going over very slight hills, etc. shoot for 16.1 - 16.4 afr (I'll also add... that the run limit for our bikes is 17.8:1) Running slab... at and below 80mph. For anything that requires a little more power, Light easy, soft acceleration, you're going to need fuel, but you can still lean it out a little for those minor needs 14.2 - 14.5 (stoichiometric) For moderate to medium loads, you have to go for the most power, this is all of the aggressive acceleration conditions, and idling, 13.1 - 13.4 Then there is the grunting power, and high rpm cool down deceleration conditions, 12.5 - 12.8 ... This leads me to ask you a few questions... like what are you adjusting this with, I assume a PowerCommander, but I think I remember you says LM2 or is that just for recording. In any even the, if it's PC, the AAP table control everything at and above 10%TP, MP is 0-9% TP. ... Please feel free to shoot me a PM, if you want to get into this a little deeper. There are lots of little details that I left out of this just to save typing and explaining time. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 25, 2012 Share Posted May 25, 2012 OH... and I forgot to mention.... when I drop down to lower elevations... my Lean AFR numbers drop slightly, do to several factors... The 16.1 - 16.4 drops down to 15.7 - 16.0 and the 14.2 - 14.5 drops down to 13.9 - 14.1 ... everything else stays the same. OH and I've never had any over heating issues.... ever, and all the pistons and plugs still look fine. Quote Link to comment Share on other sites More sharing options...
tomek Posted May 25, 2012 Author Share Posted May 25, 2012 That are surprisingly lean cruise AFRs . Anyway I have an old pc2 , had to dust off my old desktop because serial port adapter refused to adopt . Interestingly enough once I removed fuel running temps actually dropped . My theory is since most of the time you are where the MP table matters ( under 10% TP ) , by leaning out in this range ECU effectively sees higher vacuum readings and that of course leads to more ignition advance . LOL . I have LM2 with two sets of O2 sensors and cables . One set is permanently installed on my rx7 . I guess I`m gonna revisit XX and pull more fuel in areas that apply to highway cruise . Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 25, 2012 Share Posted May 25, 2012 Not super lean... I did run it even leaner than that for months, about 7% leaner than those numbers everywhere. ... PC2..... PM me your email address, and I'll send you a map. Then you can tweak it if you want. ... Now, there is only one thing about my map to know... it's designed for a 99-01 Bird. Why is that important, because there's a glitch in the 99-01 ECU programming from the factory. My PC2 map fixes the glitch. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 27, 2012 Share Posted May 27, 2012 Maybe this will be of some help to... Locating the proper TP% of opening relative to RPM, Boxes can be difficult. I finally decided on 6th gear numbers as a baseline. With the Sprockets changed to a 17/44 configuration, in order to correct the Odometer readings, I came up with these numbers... 7-8 TP @ 2600 = 45 mph 12 TP @ 3100 = 55 mph 16 TP @ 3600 = 65 mph 18 TP @ 4200 = 75 mph 23 TP @ 4700 = 85 mph Now, another important thing to remember is this... the above numbers were generated, after numerous test runs, with an already leaned out map. Why is that important? Because in order to Lean out the mixture a funny thing happens... You don't just take away fuel, and have everything else stay the same. Here's what happens. You adjust a box, taking away fuel maybe, this takes away power, power that you need to maintain said speed. Well that's not going to work.... unless you add more Air. So your Throttle Position has to open a little more.Try imagining 20% more. Now that's all fine and dandy, once you get that figured out, then add it that the PC2 program has a little blending going on. Think of the PC2 as a three dimensional plane, like the surface of the water in the ocean, and you're making a wave if you will. All the boxes are laid out on the surface of the water. If you imagine that, then you can see how the difference from one box to the next, cannot be a vertical wall. The surfaces must meet, and therefore blended together. The ECU and PC2 both work like that. They have to. So unless you want an erratic throttle response, try not to make walls. Now... all of the above only affects cruising numbers, not acceleration numbers, nor does it fix the ECU glich...... Quote Link to comment Share on other sites More sharing options...
tomek Posted May 27, 2012 Author Share Posted May 27, 2012 Yea , you are absolutely right , let`s say current AFR is 13 , you wanna get to 14.3 so you just remove 10 % , done deal right ? Well , no . You probably gonna have to redo it couple more times before you hit your target AFR . There is interpolation and linearization between cells in fuel tables , yadada . I`ve just gone thru tuning my toy car`s ECU . Stand alone ECU . I was given load based ignition map but other then that I was on my own . That particular ecu had one really nice future , I would record AFRs in spreadsheet , X rpm , Y load ( boost ) , 20x20 . It was fun but also a lots of work . Auto tune of course would be even nicer . Anyway , pm sent . We`ll see how it goes , my bike is 99 but the compression is bumped by one point , high velocity ports , and cam timing certainly is not stock . Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 28, 2012 Share Posted May 28, 2012 Oh... now we are having fun. I like it. email sent with map. Another member here has been playing with the TuneECU program on his Triumph.... what a cool program, makes me jealous, I wish we had active O2 sensors on our bikes..... yada yada.... In any event, I look forward to working with you on this.... I think it's fun. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 28, 2012 Share Posted May 28, 2012 Yea , you are absolutely right , let`s say current AFR is 13 , you wanna get to 14.3 so you just remove 10 % , done deal right ? Well , no . You probably gonna have to redo it couple more times before you hit your target AFR . There is interpolation and linearization between cells in fuel tables , yadada . , my bike is 99 but the compression is bumped by one point , high velocity ports , and cam timing certainly is not stock . Correct. in the 2, 5, and 10 TP columns... larger numbers are needed to make noticeable changes, and the changes are not linear either. What I found was in those boxes, the first 10 points removed equaled about 1 AFR ratio. To achieve a second ratio decrease you need to remove about another 8, for a third 6 ish. In the 100TP column on the other hand, also dependent on the rpm's, you might find that removing just 3 changes the AFR by a ratio. Bumped Compression.... Ooooo cool. Ya... maybe you don't want to go as lean as I am..... just to be on the safe side. ... Now for some more info... 0% TP column numbers.... Question... do you want more engine braking, or less? Add fuel in this column to increase your engine braking, and remove fuel to Decrease your engine braking. A Heavy fuel charge will be colder and denser and therefor make for a denser exhaust charge, which in turn makes for more deceleration compression resistance... ie: engine braking. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted June 15, 2012 Share Posted June 15, 2012 Progress Report ??? Quote Link to comment Share on other sites More sharing options...
tomek Posted June 16, 2012 Author Share Posted June 16, 2012 I certainly don`t care about engine braking , as little as possible would be the goal , I`m not gonna play with this on my street bike but thanks for the tip , I`ll try it on my R1 . Other then that progress has been made , I`ve gained 4-5 city / commute mpg and about 3 highway mpg . I deliberately won`t post any hard numbers because , well , YMMV . We`ll see what happens once I get into mpg favorable high elevation . I`ve essentially combined high rpm and high TP areas from Yosh map from Dynojet page with low rpm and low TP from Eric`s map . The end result was pretty good , I only had to touch up some lean 2000-3500 rpm spots at very low throttle and remove some fuel in 4500-5000 rpm 6th gear cruising . That is about it for now , the wide band O2 sensor has been removed , I may get into more detailed corrections in the fall . Now , if I could do something about those fugly bung`s welds ,,,,,,, Quote Link to comment Share on other sites More sharing options...
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