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931 fuel map for Megasquirt

 
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Petrovich  



Joined: 27 Sep 2005
Posts: 235
Location: Rockville, MD

PostPosted: Tue Mar 11, 2008 3:08 am    Post subject: 931 fuel map for Megasquirt Reply with quote

Can somebody with a relatively unmolested 931 post their VE table? (-Nick?...)
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Min  



Joined: 04 Nov 2002
Posts: 2368
Location: Vernon, British Columbia, Canada

PostPosted: Tue Mar 11, 2008 3:23 pm    Post subject: Reply with quote

Use the generated fuel map you get by typing in your motors specs/hp into the VE table generator. every car is different, variables like what kind of fuel pressure regulator and the diaphram response time will heavily change the curve. You do not want to use another person's map, it will be wrong for your motor and could damage things, start from scratch and tune your own table, It really won't take very long if you have a wideband oxygen sensor (which you should absolutely have on a turbo car)

Min
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macBdog  



Joined: 16 Aug 2004
Posts: 1111
Location: Brisbane, Australia

PostPosted: Tue Mar 11, 2008 5:15 pm    Post subject: Reply with quote

You can't really use someone else's map. Different injectors and other bits of hardware make all the difference. If you don't have a reliable AF reading it will be extremely difficult. I got my car to idle and drive without one before I thought "screw this, I'm getting me a wideband!"
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Rich H  



Joined: 10 Jun 2007
Posts: 2665
Location: Preston, Lancs, UK

PostPosted: Tue Mar 11, 2008 7:39 pm    Post subject: Reply with quote

OK mine is an N/A but what they say is true, get a WB, check all of your senders are accurate and then, tune tune, tune!

If any of your senders are suspect then fix them now. It will screw everything up in the long run. My IAT sender was out of cal by 10 degrees and that screwed up my VE table as the MS though the air was less dense than it really was. I figured I would fix it later, when I did then I had to start tuning again from scratch
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Petrovich  



Joined: 27 Sep 2005
Posts: 235
Location: Rockville, MD

PostPosted: Wed Mar 12, 2008 12:37 am    Post subject: Reply with quote

I do have a wideband; it's just that every time I generate a map, it's grossly off I was hoping that I can look at another person's map to make sure that proportionally, my map is alright. At the moment, I only have near-idle and N/A settings OK, but I'm about to start going into boost.
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Min  



Joined: 04 Nov 2002
Posts: 2368
Location: Vernon, British Columbia, Canada

PostPosted: Wed Mar 12, 2008 1:35 am    Post subject: Reply with quote

Petrovich wrote:
I do have a wideband; it's just that every time I generate a map, it's grossly off I was hoping that I can look at another person's map to make sure that proportionally, my map is alright. At the moment, I only have near-idle and N/A settings OK, but I'm about to start going into boost.


If its grossly off, that usually means one of your initial settings is incorrect. What you should do, is create a generated table, and then use your required fuel number to adjust the generated table until you get approximately 13.5:1 at idle reading on your wideband, this should put the rest of the table approximately were it should be, and will make tuning the table easier. Save a msq first though so if you can't get it working properly you can always go back to what you have right now.

Min
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1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.
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flosho  



Joined: 01 Jul 2004
Posts: 3160
Location: Eau Claire, Wisconsin

PostPosted: Fri Mar 14, 2008 1:32 pm    Post subject: Reply with quote

Just curious what size injectors everyone is running and their req_fuel and injector method (simultaneous/alternating).
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Min  



Joined: 04 Nov 2002
Posts: 2368
Location: Vernon, British Columbia, Canada

PostPosted: Sat Mar 15, 2008 1:41 am    Post subject: Reply with quote

flosho wrote:
Just curious what size injectors everyone is running and their req_fuel and injector method (simultaneous/alternating).


I'm running 21 pound blue top high impedance ford injectors, 2 squirts alternating, but I'm going to be changing that when I upgrade to ms2/extra code when the new version is released.

Min
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Petrovich  



Joined: 27 Sep 2005
Posts: 235
Location: Rockville, MD

PostPosted: Sun Mar 16, 2008 1:55 pm    Post subject: Reply with quote

WOHOOOO

Thank you all.

I just finished my first on-boost run (thirteen-to-one AFR ratio, on average). Builds up to 142 KPA, after that I stopped pushing the go pedal.

The fix to my idling was setting injectors to 2 squirts alternating. I'm using what's supposed to be 36lb/hr injectors, but they're way rich all over the map. Getting idle with 4 sqirts alternating was next to impossible, as it was either 12-1 AFR, or stall. 2 squirts actually allowed me to use the generated table after leaning it out a bit and then leaning out the idle section some more.
IIRC my req_fuel is 5, or something of that sort.

A bit more testing tomorrow, and then I'm off to the sunny Puerto Rico for a week. Just when I get things working...
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Petrovich  



Joined: 27 Sep 2005
Posts: 235
Location: Rockville, MD

PostPosted: Mon Mar 17, 2008 12:15 pm    Post subject: Reply with quote

150KPA! 6500 RPM!

Now, let me rephrase my original question....

Can I have somebody's SPARK table?
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Min  



Joined: 04 Nov 2002
Posts: 2368
Location: Vernon, British Columbia, Canada

PostPosted: Tue Mar 18, 2008 2:42 am    Post subject: Reply with quote

Hopefully someone with a 931 running megasquirt can give you their spark table. Nick?

Min
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