Tuning with AFR or Lambda?
Dec 21, 2005, 10:21 PM
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Tuning with AFR or Lambda?
I am running 100% methanol injection now and I am wondering what AFR or Lambda everyone is targeting.
I tune mine with UTEC and I had a good tune at 11.1 AFR without alky injection. I plan to target 11.1-11.2AFR with methanol injection. SInce methanol has a different stoich numbe rthan gasoline, tuning with AFR may not be the best. Should Lambda be used for more accuracy? And what AFR or lambda do you target your tune?
Stock 9.8 turbo
UTEC
3" turbo-back with Hi-flow cat
SMC kit with 100% methanol
~25psi, start tappering down from 6000RPM to 20psi at redline.
I tune mine with UTEC and I had a good tune at 11.1 AFR without alky injection. I plan to target 11.1-11.2AFR with methanol injection. SInce methanol has a different stoich numbe rthan gasoline, tuning with AFR may not be the best. Should Lambda be used for more accuracy? And what AFR or lambda do you target your tune?
Stock 9.8 turbo
UTEC
3" turbo-back with Hi-flow cat
SMC kit with 100% methanol
~25psi, start tappering down from 6000RPM to 20psi at redline.
Dec 21, 2005, 11:29 PM
#3
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I should rephrase my question...
I know that I was running 11.1-11.2 afr before alky, which is Lambda 0.76. Would it be a good lambda target if I run 100% methanol? Or should I try to target it more toward 0.85 for maximum power?
I know that I was running 11.1-11.2 afr before alky, which is Lambda 0.76. Would it be a good lambda target if I run 100% methanol? Or should I try to target it more toward 0.85 for maximum power?
Dec 22, 2005, 06:39 AM
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Originally Posted by BJai02
I should rephrase my question...
I know that I was running 11.1-11.2 afr before alky, which is Lambda 0.76. Would it be a good lambda target if I run 100% methanol? Or should I try to target it more toward 0.85 for maximum power?
I know that I was running 11.1-11.2 afr before alky, which is Lambda 0.76. Would it be a good lambda target if I run 100% methanol? Or should I try to target it more toward 0.85 for maximum power?
Too small a nozzle is just a joke and its a compromise between making good power and detonation.
are you monitoring egt?
Last edited by SlowCar; Dec 22, 2005 at 07:06 AM. Reason: are you monitoring egt?
Dec 22, 2005, 08:26 AM
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Originally Posted by SlowCar
How big a nozzle are you using? Pump enough MeOH in till detonation is non-existance so that you can tune to your ideal timing/0.85lambda/boost.
Too small a nozzle is just a joke and its a compromise between making good power and detonation.
are you monitoring egt?
Too small a nozzle is just a joke and its a compromise between making good power and detonation.
are you monitoring egt?
My car is more prone to knock than most. I could only get to around 4 deg ignition adv, 11.4afr at 4000-5500rpm running 91 octane w/o meth (21 psi). With meth, I am able to run at 25psi, 8.5 degress of timing, 11.4afr (from 4000-5500rpm), not a hint of knock.
I just want to see what most people's target lambda or afr with meth injection. What confused me is that one of the two EVOM favorite tuner suggested a pig rich AFR (~10 afr),l while the other tuner suggested 11.2afr. Any suggestion?
I don't have an egt yet, but it will be installed soon.
Dec 22, 2005, 10:57 AM
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Originally Posted by BJai02
I am using the default nozzle that came w/ the kit, M7.
My car is more prone to knock than most. I could only get to around 4 deg ignition adv, 11.4afr at 4000-5500rpm running 91 octane w/o meth (21 psi). With meth, I am able to run at 25psi, 8.5 degress of timing, 11.4afr (from 4000-5500rpm), not a hint of knock.
I just want to see what most people's target lambda or afr with meth injection. What confused me is that one of the two EVOM favorite tuner suggested a pig rich AFR (~10 afr),l while the other tuner suggested 11.2afr. Any suggestion?
I don't have an egt yet, but it will be installed soon.
My car is more prone to knock than most. I could only get to around 4 deg ignition adv, 11.4afr at 4000-5500rpm running 91 octane w/o meth (21 psi). With meth, I am able to run at 25psi, 8.5 degress of timing, 11.4afr (from 4000-5500rpm), not a hint of knock.
I just want to see what most people's target lambda or afr with meth injection. What confused me is that one of the two EVOM favorite tuner suggested a pig rich AFR (~10 afr),l while the other tuner suggested 11.2afr. Any suggestion?
I don't have an egt yet, but it will be installed soon.
I got a custom tune from Al last week and A/F ratio is 10.9 to 11.1 with methanol throughout. When boost was at 24-25 psi, there was a hint of knock so he turned the boost down. There was still a slight knock (about 1.1V) at 23.5 psi so he took out a degree of timing. Knock voltage stays under 0.80V now.
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Dec 22, 2005, 11:00 AM
#8
Originally Posted by KevOVIII
My car is also prone to knock on 91 at 21 psi. There are slight knocks at about 6500 and 6900 so I had to lower boost to 20-ish.
I got a custom tune from Al last week and A/F ratio is 10.9 to 11.1 with methanol throughout. When boost was at 24-25 psi, there was a hint of knock so he turned the boost down. There was still a slight knock (about 1.1V) at 23.5 psi so he took out a degree of timing. Knock voltage stays under 0.80V now.
I got a custom tune from Al last week and A/F ratio is 10.9 to 11.1 with methanol throughout. When boost was at 24-25 psi, there was a hint of knock so he turned the boost down. There was still a slight knock (about 1.1V) at 23.5 psi so he took out a degree of timing. Knock voltage stays under 0.80V now.
Thanks
Dec 22, 2005, 11:06 AM
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Originally Posted by Ev0ikon
What are you reading this Knock voltage with? And is this voltage in reference to the usual 0-5.0V ?
Thanks
Thanks
Dec 22, 2005, 03:44 PM
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Originally Posted by KevOVIII
My car is also prone to knock on 91 at 21 psi. There are slight knocks at about 6500 and 6900 so I had to lower boost to 20-ish.
I got a custom tune from Al last week and A/F ratio is 10.9 to 11.1 with methanol throughout. When boost was at 24-25 psi, there was a hint of knock so he turned the boost down. There was still a slight knock (about 1.1V) at 23.5 psi so he took out a degree of timing. Knock voltage stays under 0.80V now.
I got a custom tune from Al last week and A/F ratio is 10.9 to 11.1 with methanol throughout. When boost was at 24-25 psi, there was a hint of knock so he turned the boost down. There was still a slight knock (about 1.1V) at 23.5 psi so he took out a degree of timing. Knock voltage stays under 0.80V now.
What kind of timing do you see at mid range (like 4500 rpm) and at 7000RPM?
Dec 22, 2005, 09:42 PM
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Originally Posted by BJai02
Do you happan to have a datalog file of your car? I am interested to see it.
What kind of timing do you see at mid range (like 4500 rpm) and at 7000RPM?
What kind of timing do you see at mid range (like 4500 rpm) and at 7000RPM?
Dec 22, 2005, 11:02 PM
#12
Originally Posted by KevOVIII
There was still a slight knock (about 1.1V) at 23.5 psi so he took out a degree of timing. Knock voltage stays under 0.80V now.
Dec 23, 2005, 10:08 AM
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Originally Posted by razorlab
Was it a spike of knock voltage from .8 to 1.1v? Because 1.1v is about normal engine noise on my car for about 4k and up. When I get knock it spikes to almost 2.0v or above.
Side note: I noticed that AFR was about 0.2-0.4 richer (from 7k+) the next day when I was fine tuning the car... compared to the previous day when Al was making pulls. 10.9 turned into 10.5 at some points.
Dec 23, 2005, 10:14 AM
#14
Originally Posted by KevOVIII
Side note: I noticed that AFR was about 0.2-0.4 richer (from 7k+) the next day when I was fine tuning the car... compared to the previous day when Al was making pulls. 10.9 turned into 10.5 at some points.
Dec 23, 2005, 10:21 AM
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Originally Posted by razorlab
Yea amazing what weather changes do eh?
May I ask what gas you're using? I've been using Chevron but have seen and heard from others that 76 is better.