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Old 07-23-2008, 03:34 PM   #21
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Naarleven. Ummm. Funny. Ummm. Huh?

Last edited by cueball1; 07-23-2008 at 08:20 PM.
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Old 07-23-2008, 04:19 PM   #22
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yeah i do see what DIY is saying...you probably idle around 34 kPa?....you jump from 34 to 55kPa in your rows, with a big jump from 48 to 64 VE in the table. I could see that pwning your idle quality.

you can see what i did....my map only has 3 boosted rows:
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Old 07-23-2008, 08:19 PM   #23
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Idle's around 28-30 kph. I'm looking at reducing the lower ends of the VE tables to low 40's instead of high 40's and see what that does. If the VE table is calling for too much fuel I would guess the car goes rich and then cuts. The opposite could also be true.

Might explain what's happening. Might not. I'm new to this tuning stuff obviously. I'll be trying changes to the VE table tonight and see what happens.
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Old 07-23-2008, 09:56 PM   #24
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this is why i added the 45 row, the jump between the 50 and 32 row fucked my idle...
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Old 07-24-2008, 09:47 AM   #25
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That is what it sounds like to me. Its just bouncing back and forth between two cells that are hard to interpolate between.

If you look at Brain's VE table, you'll see how different the numbers are in that range.
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Old 07-25-2008, 02:14 AM   #26
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what's the math for calculating what numbers to put in each cell if you were to make a new row in the middle of two existing rows?
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Old 07-25-2008, 05:07 AM   #27
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What you are looking for is interpolation. Excel can do this in a 2d fashion.

I am still looking for a nice program that will take a large map like the 16x16 AFR table used in MLV and let you choose values for XY and have it give you Z it would be very useful for scaling it perfectly into the MSQ table.
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Old 07-25-2008, 08:16 AM   #28
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I have just had an insane idea. So insane it might just work.

We have limited resolution and ATM Brain thinks you dont have enough rows at the bottom to idle smoothly. Brains map also only has 3 rows for boost fine but we want more.

Ok here's the mad part. Cook up a table for NA operation top row at 105kpa. Write a second table for boost bottom row at 105 kpa. Put this table in VE table 3 then tell Output 2 (X5 JS3) to trigger at a MAP reading of 105 kpa. Wire the output to a small transistor circuit the output of which shorts Pin6 JP1 to GND. Now when you hit the top of the VE table 1 you will switch into the boost table.

Discuss
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Old 07-25-2008, 08:41 AM   #29
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I bet I could make due with one row for boost. I dont see the point. But it would probably work.
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Old 07-25-2008, 09:11 AM   #30
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So bigger tables not needed/desirable?
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Old 07-25-2008, 09:46 AM   #31
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since I hold boost flat to redline, once spooled I'm only reading straight across "one" row to redline.

Between 105kPa (.5psi) and 128kPa (4psi), the table smoothly gets me to my target of 12.2ish in boost. Between 128 and 184 (12psi, where I run) I maintain the richness. I have one row above my boosted row (212kPA | 16psi) to deal with boost spikes, cold days, or if I'm feeling adventurous.

Everything below that is for cruise. I absolutely had to as I had lots of spots where I would be at 60kPa but only have rows for 55 and 75kPa and the jump between the both was enough to make my AFR go batty, enough that even EGO at 15% couldn't handle it. Since I rescaled my fuel table, I have super resolution in cruise and enough that when I'm in boost I have no worries. I have a perfectly smooth idle as a result as well, since I idle at 32kPa I have a row for it, and only a small jump in change above and below it.

You'll also notice I have no 100kPa row, I'm just above it, and the row below it 85. I chose to do this as I have yet to cruise higher than 80kPa or so. But on my targets table I still target 14.7:1 at 100kPa. This allows me to blend in fuel only after I'm making boost, and I can still allow for a lean cruise even when I'm at low vacuum. The transition into boost is smooth as butter.
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Old 07-25-2008, 10:01 AM   #32
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EBC & quick spool FTW eh.

Do you use any tools for table scaling like I mentioned in my previous post or is it done by guess and god?

I suppose the clever ******* who write bits of the extra code could repurpose the memory used for VE3 to make one larger 16x16 table like in MS2 but I think if someone desperately needed a bigger table then my idea could be useful.
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Old 07-25-2008, 10:14 AM   #33
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Started with the diy map as a base, when i got the tune fairly close. I simply copied the numbers into Excel. Then I decided when I wanted smaller steps. added a blank row in between them and used the formula ( =(C1+C2)/2 ) so I had good value to use.

I did the same when rescaling a map on a MSPNP that was utilized for ITBs:
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Old 07-25-2008, 11:32 AM   #34
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so add the cell above and below the new blank cell and divide by two? That's math even i can handle. Thanks
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Old 07-26-2008, 12:21 PM   #35
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Being a little nervous about cutting out boost rows, I stole one boost row and evened up the vacuum rows.

That and some MS tuning basics are helping. I'm logging EVERYTHING. Log, tune, log, tune, log, tune. Then I'm looking at the VE table while driving to see where it is commonly jumping cells and can use some smoothing . Car is much better. Not 100% yet, but much better. I'll likely steal away another row from boost for additional smoothing.

Best advice a newb to MS can give to others of my kind, log and tune like crazy.
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Old 07-26-2008, 05:39 PM   #36
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have you ever watched a log in MLV when you get into boost? you'll quickly see why it's not a big deal....80% of it is unutilized.
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Old 07-30-2008, 10:41 PM   #37
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for those of us not schooled in excel and making spreadsheets I found this program http://www.softpedia.com/progDownloa...oad-37726.html
that lets you go cell by cell and interpolate between known values.
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