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Old 03-04-2010, 06:01 AM   #1
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So yeah, my fuel economy sucks *****. I can get 21 MPG if the tank is mostly highway driving and I drive like a grandma.

I'll post up pics of my fuel and ignition maps shortly.

My setup is a 99 with a 2002 bottom end (10:1 compression), JR M45 @ 6-7psi, Adaptronic e420c tuned by a respectable tuner, JR water-to-air intercooler, JR headers, Magnaflow rear muffler (2.5" all the way), RX-7 460cc injectors recently cleaned and flow tested.

It made 167hp on a Dyno Dynamics.

I don't have any blowby and I have a catch can between my PCV valve and intake manifold, so it's as clean as a whistle.

I'm not using any fluids, everything seems fine engine wise. The only known mechanical problem is the gearbox - it sounds like it is out of a rally car.

Any ideas?
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Old 03-04-2010, 06:43 AM   #2
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Fuel:



Ignition:

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Old 03-04-2010, 06:46 AM   #3
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The supercharger bypass valve has recently been replaced, so that should be OK.
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Old 03-04-2010, 09:08 AM   #4
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Is there an AFR target table on the Adaptronic? I don't see a big problem here, but perhaps you are just running rich at cruise. Or you have a big friction problem elsewhere, sticky brake, or that tranny noise.
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Old 03-04-2010, 09:48 AM   #5
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What's your AFR at cruise?
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Old 03-04-2010, 10:36 AM   #6
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I say your running too rich at cruise, I had the same problem before and I just leaned out my cruise rows to around 14.7-15
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Old 03-04-2010, 11:50 AM   #7
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fuel table is meaningless. post AFR target table.
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Old 03-04-2010, 12:01 PM   #8
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Is your ign locked at 10deg from setting your base timing? That would own your MPG.
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Old 03-04-2010, 01:17 PM   #9
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Is your ign locked at 10deg from setting your base timing? That would own your MPG.
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Old 03-04-2010, 01:44 PM   #10
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Can you guys not rescale your tables to provide better resolution in the areas you actually use? Every adaptronic table I see goes up to 300kPa... Seems to me that it would be possible to gain at least 4 rows and 2 columns towards increasing resolution and helping the table transition in areas where VE does not change linearly.
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Old 03-04-2010, 01:45 PM   #11
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We need to see target afr's and a log or two of cruise as well as wot. fuel maps alone are useless.....That said I'm still working on fine tuning my fueling, and its 26-29 (city) driving normally, and about 20-25 getting on it and boosting all the time. Not bad but there's room for improvement imo.
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Old 03-04-2010, 01:46 PM   #12
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Quote:
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Can you guys not rescale your tables to provide better resolution in the areas you actually use? Every adaptronic table I see goes up to 300kPa... Seems to me that it would be possible to gain at least 4 rows and 2 columns towards increasing resolution and helping the table transition in areas where VE does not change linearly.
Pretty sure we can't change what kpa it goes up to. I may be wrong
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Old 03-04-2010, 02:01 PM   #13
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Quote:
Originally Posted by Ben View Post
Can you guys not rescale your tables to provide better resolution in the areas you actually use? Every adaptronic table I see goes up to 300kPa... Seems to me that it would be possible to gain at least 4 rows and 2 columns towards increasing resolution and helping the table transition in areas where VE does not change linearly.
you can, but then you have to re-tune... it's just a pain.

it's still evenly spaced.
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Old 03-04-2010, 02:51 PM   #14
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You can't just change the max kpa value to slightly over your max target? Won't the graphs just fill in with the interpolated values?...I guess those would be slightly off though.


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Old 03-04-2010, 03:24 PM   #15
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It fills it in TO THE BEST OF ITS ABILITY. which, quite frankly is not good enough.

I tried to mess with mine, but gave up cause its just not worth the hassle.
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Old 03-04-2010, 04:04 PM   #16
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it does nothing. if you change that number to some smaller value, the left hand colum will change and that's it. you'll seriously overfuel your ****.

it will jack up your spark table

it will also jack up your AFR targets.

and what sucks most is that there is no FAST way to fix it. You have to go in and edit every cell individually.

so as much fun as that sounds...
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Old 03-04-2010, 04:35 PM   #17
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/\ haha I already went through my tables 3 times EACH cell individually when ironing out the fuel/spark the last few times.

SCREW THAT lol
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Old 03-04-2010, 04:56 PM   #18
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Is it ok if I am tuning for 180kpa and set my my kpa value just above that? Is it when your change that value after you've already done tuning that software screws up that value?
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Old 03-04-2010, 05:27 PM   #19
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I'm aiming for stoich at cruise, because I'm just running a narrowband sensor I can't target anything else anyway. Here's my target table:



It could be the transmission I guess, the brakes are all good though.

I'll do some datalogging and report back, thanks guys!
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Old 03-04-2010, 05:34 PM   #20
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Narrow band = completely useless

14.7 AFR at 150 kPa = ******* insane
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