E85 for smog?
#1
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I don't know if this is the right section, but I am trying to help a friend pass smog and it passes the hydrocarbon and the CO emissions no problem but the nox is more than double what the max should be. I was thinking about draining his tank and filling it up with E85 and retuning the MS. Does anyone have any Idea how this would affect the nox or any other way to reduce the nox emissions. The car has a new 3way cat so that is covered. O ya and it has a stock greddy kit.
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Oh good, so you know everything.
Just in case you don't, try this.
https://www.miataturbo.net/search.php?searchid=1637855
Just in case you don't, try this.
https://www.miataturbo.net/search.php?searchid=1637855
#6
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Oh good, so you know everything.
Just in case you don't, try this.
https://www.miataturbo.net/search.php?searchid=1637855
Just in case you don't, try this.
https://www.miataturbo.net/search.php?searchid=1637855
#7
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From a local forum, when the guy's car was failing on pumpgas. Might help ![Dunno](https://www.miataturbo.net/images/smilies/dunno.gif)
![Dunno](https://www.miataturbo.net/images/smilies/dunno.gif)
I PASSED!!!!!!!!!! I put in a can of denatured alcohol, installed the cat, leaned it out -15 from 3000rpm to redline, disconnected the wastegate arm, and new spark plugs. My numbers were almost zero across the board:
Before:
HC 2.4033 limit was 1.200
CO 29.2839 limit was 20.0000
NOx 3.6542 limit was 3.0000
After:
hc 0.8017/1.2000
co 7.2814/20.0000
nox 0.9723/3.0000
Before:
HC 2.4033 limit was 1.200
CO 29.2839 limit was 20.0000
NOx 3.6542 limit was 3.0000
After:
hc 0.8017/1.2000
co 7.2814/20.0000
nox 0.9723/3.0000
#9
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9 out of 10 of the locals on e85 barely squeak by on it when testing, and rarely on their 1st pass. It seems as though a good, slightly lean tune on pumpgas gets by easier. Is he failing on pumpgas or e85 right now? From your first post it sounds as though he's on pumpgas. Either way, smog it on whatever will make it pass, then run e85, and drain and run the "smog recipe" next time he has to test.
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CA + passing smog with MS = This thread is relevant to my interests.
As much as he wants to run E85, I think this will be way easier with pump gas. Do a google search and nox and what changes it. From what I hear, nox is the hardest of the 3 to get right.
As much as he wants to run E85, I think this will be way easier with pump gas. Do a google search and nox and what changes it. From what I hear, nox is the hardest of the 3 to get right.
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Yes I did google and found mostly that is reduces nox 25-31% sourced from GM, EXON, wiki, turbo bricks, and LS1 tech. he is interested in running E85 for its performance advantages, and figures if it helps nox just do it now, Ive done smog tunes for many a car on pump gas, normally the recipe in CA is to pull timing (a lot) in the range of the test, since you are on a dyno. and make sure it is running as close to stoich as possible has worked in the past. I found it interesting that matthewdesigns said "I put in a can of denatured alcohol" this would basically be using E? because we dont know the % of the alcohol that was used. Im looking for tuning for smog with E85. It just doesn't seem like anyone does it.
#15
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Higher EGTs cause more NOX so less timing will help.Going leaner will raise NOX but should lower HC and CO. EGR valves are meant to lower NOX emissions, but that is usually one of the first things people take off. Water meth kit without increasing timing might help but I don't know.Where I live they don't do smog tests so I really couldn't tell you for certain.
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Higher EGTs cause more NOX so less timing will help.Going leaner will raise NOX but should lower HC and CO. EGR valves are meant to lower NOX emissions, but that is usually one of the first things people take off. Water meth kit without increasing timing might help but I don't know.Where I live they don't do smog tests so I really couldn't tell you for certain.
From what I've seen, retarding timing raises EGT's. Nearly melted some stuff myself from retarded timing (Don't ask).
#19
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Could run an Adaptronic, it uses the GM fuel sensor, and will automatically scale your fuel output based on ethanol content. Easy to gas and back, and no creating whole new maps. :X
Also, I would be willing to bet your running to much advance. The NOX is only created under high cylinder pressures. Due to the ethanol giving you much higher cylinder pressures before detonation you can generate a lot more NOX with E85.
Also the Patrick the owner of Innovate (which he sold it) started a new company called EmiSense to develop a different line of sensors which includes a NOX sensor... I don't know if its done yet, but at SEMA he said they were close to a commercial product.
Also, I would be willing to bet your running to much advance. The NOX is only created under high cylinder pressures. Due to the ethanol giving you much higher cylinder pressures before detonation you can generate a lot more NOX with E85.
Also the Patrick the owner of Innovate (which he sold it) started a new company called EmiSense to develop a different line of sensors which includes a NOX sensor... I don't know if its done yet, but at SEMA he said they were close to a commercial product.
#20
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I bet Id have a hard time convincing my friend that he needs to buy a new stand alone to run E85, I think he only has 3-4K on his MS over the 2 years he has had it. But that sounds really cool.
"Also, I would be willing to bet your running to much advance. The NOX is only created under high cylinder pressures. Due to the ethanol giving you much higher cylinder pressures before detonation you can generate a lot more NOX with E85."
This is more along the lines of what Im looking to learn about E85 here, So I know his smog map was just his standard 91 timing map with the timing pulled down so it is not a map advanced for E85. So using that map would there be a reduction?
I dont want to spend a lot of time on this smog ordeal, I hate smog checks. Just trying to help a friend out, if the E85 wont work I will just tell him that, I just need to be able to tell him something other than some guy on the forums friends evo did this with E85 and it didnt work.
"Also, I would be willing to bet your running to much advance. The NOX is only created under high cylinder pressures. Due to the ethanol giving you much higher cylinder pressures before detonation you can generate a lot more NOX with E85."
This is more along the lines of what Im looking to learn about E85 here, So I know his smog map was just his standard 91 timing map with the timing pulled down so it is not a map advanced for E85. So using that map would there be a reduction?
I dont want to spend a lot of time on this smog ordeal, I hate smog checks. Just trying to help a friend out, if the E85 wont work I will just tell him that, I just need to be able to tell him something other than some guy on the forums friends evo did this with E85 and it didnt work.