AFR/Timing/Fueling question
#1
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Hey guys, I want to start focusing on fixing my fuel map (it's pretty ugly right now) and was hoping folks could look at my AFR target and Timing maps so I know they're right before I start adjusting fueling. From what I'm hearing on fueling it should be going up in a linear fashion, however I don't want to play with the fuel map until I'm sure everything else is OK. I attached my fuel map for kicks if anyone wants to advise me on this. I'd like to avoid going to a Dyno this time, I'm tired of paying for peak power and having shitty cruising fuel economy.
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So, there's no VEA or VEAL for a Hydra? ![Giggle](https://www.miataturbo.net/images/smilies/gay.gif)
Your AFR table doesn't make sense to me. Some areas have sensible values like 12:1 and 14:1. Other areas have gibberish like 0.5:1 and 43:1. What's up with that?
Do a search for AFR tables. There are threads with good examples along with discussion of why you use certain AFR's in certain operating areas.
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Your AFR table doesn't make sense to me. Some areas have sensible values like 12:1 and 14:1. Other areas have gibberish like 0.5:1 and 43:1. What's up with that?
Do a search for AFR tables. There are threads with good examples along with discussion of why you use certain AFR's in certain operating areas.
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Oh shoot yeah the AFR table and Timing table CSVs are backwards (AFR table is the timing table, and vice versa). I tried using interpolation to clean up my fuel map, but it gutted some sections so deeply that they would likely have very lean cells.
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I don't run that lean at idle, but run leaner in cruise(15.5-16), and I think you can run leaner in your under 8 psi boosted cells(~12.2-12.7). I didn't look at anything else yet because I'm driving.
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I have trouble idling smoothly at 900rpm and anything more than ~14.7, but anything 1250+ and in a vacuum cell was adjusted leaner (target of 15.6, might bump it up even more), as was boost up to 6psi (target of 12.2:1, 7psi has 12:1 and 8 has 11.8:1).
Car runs surprisingly well in cruise for running so lean, just need to go through a tank without any ignition issues and I should have some improved economy. My last mostly freeway tank I got 22mpg, if I can get 24 I'll be happy. If I break 26 (doubtful) I'll be back to the worst mpg tank I had prior to converting to turbo.
Car runs surprisingly well in cruise for running so lean, just need to go through a tank without any ignition issues and I should have some improved economy. My last mostly freeway tank I got 22mpg, if I can get 24 I'll be happy. If I break 26 (doubtful) I'll be back to the worst mpg tank I had prior to converting to turbo.
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Some of the economy might be from your timing too. Joe has a good thread where he adjusted his timing in the cruising cells for fuel efficiency. Basically, the closer you are to MBT the better economy you will get (which makes sense, a more complete burn, more torque).
IIRC he was datalogging pulsewidth to help him determine if a change resulted in better or worse economy.
IIRC he was datalogging pulsewidth to help him determine if a change resulted in better or worse economy.
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