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I know this is quite a different fuel to 98 octane petrol. I have gathered stoich is around 9.7 or 0.9 lambda .. at wot I am thinking around .80 lambda. What are the target lambdas on light medium throttle? Am I on the right track for wot and idle stoich? If this were normal fuel I would be sweet..any input appreciated
Stoich is 1.00 lambda no matter the fuel.
Kyne is correct.
I currently use 9.87 for Stoich with E85, Running on the united pump E85. Theoretically your target lambda in the base fuel table doesnt need to change.
I was running .79-.78 uptop on pump 98 but Ive heard if guys lifting cylinder heads at that lambda or richer with big boost ie25psi and above. Im currently running in the zf I've just built but when i decide to retune I will will try a few different target lambda values to see what achieves the best result,with about 23psi
The lambda is always the same for different fuels as I understand it. I don't want to go to 25psi as it is a daily driver . I will try 9.87 stoic and yes I found e85 from united quite good. I targeted a leaner 0.82 lambda on wot on pump fuel the car goes good. Hmm I wonder if I can also go leaner on light load light throttle to get better fuel economy as an experiment ON E 85. This will be interesting and most of all fun:)It is currently getting 24 l/100 consumption untuned at the moment so see if I can flesh out idle leaner part light throttle because while I am impressed amazingly with the extra punch of this magic fuel it can be an inconvenience refueling more often. See how I go and may share a few tips to help others because I see most people are reluctant to share a few ideas. That is ok I will :)
Thanks for the input so far guys.
This would be a guide only, but will get you close, really close actually. Lambda, E85, Gas
0.730 7.125 10.731 @ Max Power Multi Turbo
0.740 7.222 10.878
0.750 7.320 11.025 @ Supercharged/Turbo
0.760 7.418 11.172
0.770 7.515 11.319 @ Max Power NA
0.780 7.613 11.466
0.790 7.710 11.613
0.800 7.808 11.760 @ Consistant Race
0.810 7.906 11.907
0.820 8.003 12.054
0.830 8.101 12.201
0.840 8.198 12.348 @ Part throttle RACE
0.850 8.296 12.495
0.860 8.394 12.642
0.870 8.491 12.789 @ Idle
0.880 8.589 12.936
0.890 8.686 13.083
0.900 8.784 13.230
0.910 8.882 13.377 @ Part throttle STREET (economy)
9.76 would be lambda
.77 for Max power NA? I would check your numbers.
Just a guide guys, meant to be a starting point. Get it on a dyno asap after and find what the engine wants to dial it in. Although, I think you will find the boosted #'s to shoot for are quite accurate in that chart
Why would you want idle anything but Stoich? In my experience it should be this
Idle/part throttle/cruising - 1.00
Max power NA. ~.88
Max power supercharger. ~.78
Max power turbo .72-.75
I think your multi turbo is correct but I think the others are off by quite a bit. Turbo is a bit harder to say an exact one, and the rest are approximations but I would say those are good starting points and where I start to tune from. The last LS9 I did I leaned out to .79 at max power.
Couple days ago, LS1, 12lbs, Meth, E85... best power was at .74 leaned out to .76 up top. So it's a pretty good ballpark I thought as well. The chart is originally from the engineers at Honda, and they too advise it is for a starting point only
Thanks for the input guys. Over time it is what each setup wants. Different cars setups will perform best on their sweet spot Tuning from a safer starting point then slowly making changes is the way. I have avoided dynos but actually use the 1/4 mile track so far to measure results and log. Yes I know I am taking the long way but it works for me while having the enjoyment to run it at same time:)
To figure what lambda You need, EGT is a must, this with dyno puls (or better road or 1/4 mile) WOT while logging timing (knock) and EGT will tell You. For me it's a must in modified engine. You don't need that when You do second identical setup, but any new - buy EGT, cheap insurence.
Without that, You never know where You are.
Some example, lower timing (lot of people do that in non build engines while boosting them) makes EGT much higher than when it could be when timing set for max power, then You must make it more rich to compensate. When You do correct timing, You can go leaner, in this case making more power and have safe EGT.
When engine is forged, You can do nearly what You want, Your best lambda will be lambda vs timing making best power with EGT You want.
I've seen some custom tunes delivered with SC or turbo kits with not really much boost (5-8psi) that were at 0.82 and EGT was 300F more that N/A.
Making it 0.79 bringed EGT to n/a level (safe timing).
Another mustang with turbo, safe timing, 10 psi. lambda 0.79, close to stock EGT, same car with build engine, timing set to max power and final lambda at 0.83 (so leaner) and EGT close to stock.
I was under the impression .82-.85 Lambda was optimal for NA applications to be safe but still make power.
Theres been a huge problem with the new Coyote motor in the 11-13 Mustang GT's tossing #8 cylinders due to improper fueling. They like 11.9AFR up top to be safe.
Stav and Canigga make a very valid point - one that can be applied to saying there is no blanket Lambda and every application is different.
Speaking of the #8 cylinder problem. I do not believe the problem is fueling related. Rather, it is from improper tuning, IE using global spark adder.Quote:
Originally Posted by Gremlin85
Ah, gotcha! Thanks Eric!Quote:
Originally Posted by Eric@HPTuners
I was just going by what some SCT tuners have mentioned. I am anxious to open up my 2013 GT and see whats what as far as tables and tuning abilities go. I have never touched SCT so these are completely new for me :)
I would think it's like the LS engines, the back cylinders run lean or are too hot so they need more fuel to compensate for that cylinder.Quote:
Originally Posted by Eric@HPTuners
And I agree there isn't a blanket lambda setting for max power, depends on the engine design. Apparently the DI engines like leaner mixtures according to that other vette thread, but the settings I posted are what I start with and usually I don't even change them.
Kyne and Eric a question. In those instances where you know you have a certain cylinder leaner/hotter than the rest, without the ability to control injectors individually or spark for that matter, only globally. I can't really think of a solution.Quote:
Originally Posted by Kyne
I Dont believe calibration of the knock sensitivity in relation to cylinders is the answer. Would it not be better to have consistance spark for each cylinder and be able to injectors individually? I dont believe we have that ability with the australian fords as logging the EGT's for each cylinder is on my to do list.
Knock adjust is not all, you can have knock ok, but cylinder melted, maybe in coyote is this problem, I don't know.
I'll add some info for per cylinder tuning as I was in situation I needed quick solution to fix the problem.
If in the car is one egt, simplest solution will be compare temperatures of single cylinders.
It can be done directly at exhaust just after wot run, switch off engine as fast as possible, what in long term is not good and not pretty acurate anyway (but easiest), and use laser meter. I used laser meter with USB hanged inside engine compartment and directed to cylinder I want, but with USB connection and constant metering option, to see on the fly and that's very acurate. Then I was able to adjust mixture of worst cylinder at first to match temp of rest, of course if there is available correction of single cylinder. I did this so with aftermarket ecu's (VEMS) that had such correction in one rally build having problem with overheat one cylinder due bad intake design (problem after engine was boosted).
Second option is old school method is watching every spark plug after such run.
And third option without measuring temp for every cyl is leaning mixture or advancing timing till you see knock activity and then riching cylinder having problem (if You have knock that shows every cyl). All till all cylinders will react similar for leaning or increasing timing. But you have to be sure engine will handle those experiments in short time...
Fourth, dyno tune for best power at every cylinder, changing only mixture (after it, You can do same with spark if such option available).
When You get into detonation, CHT will grow up and EGT will fall down, EGT should grow with rpms. Since knock sensor are acurate, this is marginal problem ( I was reading about, but i've never experienced this).
There is some topic on another forum (can't find it now), where man states that he's tuning single cylinder in Mustang via SCT and gaining more power from that. I have no SCT, so can't tell if there really such option is.
So if there's not such solution, as per cyl correction, then there must be rich mixture to satisfy one cylinder, then all 7 cylinders are under powered (or use piggy back with that option, just to fix this).
And one more about EGT, it's good to have base for compare, eg before mods.
Having egt for all cylinders is of course best option...
Hiddeous, chime in now, and let the boys know what that table is in SCT
Well after all that I realised my injectors are not up to the job with e85 so went 98 premium fuel coupled with the fact that the fuel economy had me looking for a fuel station to fill up every 230 killometers the 98 fuel gets me almost double the distance. Still went to the track last week tinkered a little more and pulled 12.3 1/4 . Just got one run with the fresh tune so might go one day again see how she goes
that is a nice effort..what sort of MPH?
Before I went to E85 i was on pump 98 with the stock turbo making roughly 490rwhp running 11.6@120mph on street tyres. Having a heap of issues with the ZF as it wouldnt shift 3-4th at WOT.
After that went to E85 and a rough tune as was running out of pump and went 603rwhp @ 19psi with a GTX3582r but haven't race it yet at Ive just rebuilt the box and im trying to fix that no shift issue.
230km's is pretty low. I know E85 economy is poor but even on my 600hp tune I get atleast 320ks to a tank around town. I haven't run it on the highway yet.
Check the 02 sensor signals, you might have a crook one.
Eric, what exactly are you saying here? People are actually using the global spark adder as a tuning device? I have used SCT for years now and tuned many Coyotes. There are some minor differences in these but basically the same animal. I have seen that they are a very sensitive engine and have normally ran them on the rich side and completely take away the pcms ability to add timing thru the knock sensors(especially in forced induction cars).Quote:
Originally Posted by Eric@HPTuners
Yes, because they did not understand the complexity of the new spark tables, a 5 degree global spark adder was used. In my personal opinion, this is the most probably reason for many of the failures.Quote:
Originally Posted by Badassbird
Hi mate sorry for late reply. I went 112.2 mph and about 93 mph half track. I would love to get 320 a tank around town. Set stoic to 9.7 wot 0.80 lambda. Im going to play with ignition timing because I have a feel fuel economy is better with more put in safelyQuote:
Originally Posted by 45T-XR
Use 9.87 for stoich ratio and recheck your WOT lambda. are you commanding .8 in your base fuel table?
Currently 9.7 stoich and wot is 0.80. Ill change it to 9.87 see how she goes.
so when you go 9.7 for E85, no more closed loop with the standard oxygen sensor. Is this right?
If the right stoich scalar is used your trims will not change much. There is no individual cylinder fuel tuning for the BA/BF. There appears to be a table in SCT but this is actually the battery offset table presented very unusually.
Thanks Brendon. I just thought the stock O2 sensor would not work at 9.7:1 in closed loop with E85. I thought the stock sensor could only do 14.7 ratio. Nevertheless I am putting a tank of E85 in soon to suss it out.
Stock o2 is a lambda sensor not an AFR sensor. It's set up to read 1.00 lambda.
Thanks, it makes sense now
By targeting 1 lambda the stock o2 sensor will still target 1 lambda because it measures the oxygen content value regardless of fuel
Thanks guys. I should have worked this out myself but I have 100000000 things on my mind ATM.
I put my first tank of E85 in today. Changed the stoich to 10 for the moment (still about 10l of BP98) and runs sweet just cruising around.
The exhaust air is just so much cleaner. It feels good having 105 Octane.
Has anyone got a proven high boost ethanol tune they can post to have a look at.
Drop around mine and we'll sort it :-). Poison that tree on your way down the driveway!!!
I've got some stuff that was banned about 25 years. It might do the job for the tree.
Hahaha sounds perfect!!!
I'm in the same boat as you trana, I bought the zeitronix ethanol sensor kit, and I have created an excel sheet which will tell me what to put in as Stoich if I tell it what thanks percentage it's running. If anyone has any info on what else I can do that the e85 likes, would be appreciated
Thanks, Joe