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Old 12-30-2007, 09:46 PM   #1
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Default Scaling VE Tables

The thread hustler made got me thinking.

The PNP VE table is scaled all the way to 18 psi or 230kpa. I dont plan to run that much. Probably 12 psi at the most.

What would happen if I took the PNP fuel table and rescaled the KPA's to only go up to 200KPA while keeping the VE values in the table the same.

Would it give me more accuracy in fuel delivery or would it screw it up completely?
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Old 12-30-2007, 09:52 PM   #2
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It wouldn't mess it up, you would end up too rich most likely across the board. You would have better resolution throughout which is nice. So yeah, just figure out the max boost you will ever run, ad 8-10 psi for some room for cold day overboost and then go tune the NA part while you can.
I think Arkmage brags about only using 4 rows for the N/A portion of his fuel table.
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Old 12-30-2007, 09:59 PM   #3
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Makes sense. It almost makes no point to do it I think because the table maxes out at 18psi, and I plan to run 12 plus headroom for cold days so I think ill keep it.
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Old 12-30-2007, 10:10 PM   #4
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That's a bit much headroom sam. It's up to you though. You'd be better off making the max 200 and just go out tuning. It's not like you're un familiar with tuning it now. Either way. You should format it so you use as much of the table as possible.
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Old 12-30-2007, 10:26 PM   #5
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Quote:
Originally Posted by cjernigan View Post
That's a bit much headroom sam. It's up to you though. You'd be better off making the max 200 and just go out tuning. It's not like you're un familiar with tuning it now. Either way. You should format it so you use as much of the table as possible.
Maybe youre right.

I just need to do some guess work before hand. Figuring out what numbers to fill in and all.
Where do I want more resolution, in boost or NA? How do I know how much of the table to dedicate to NA and Boost? and the Scale.
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Old 12-30-2007, 10:37 PM   #6
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You have 12 cells split them in half, 16.6 KPA per row. Round as you see fit. It's not rocket science sam. You could run the NA portion with four rows and dedicate the rest to boost if you wanted. But you might as well run 5 or 6. Set the first two rows according to your idle KPA and cruise or w/e you feel like. Make one dead on with your low idle KPA though, keeps it in one cell. Then make one for low load cruise KPA, crap like that. Scaling isn't going to be that important.
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Old 12-30-2007, 10:39 PM   #7
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Just realized, what about the spark table? That one is going to need to be scaled too, according to the VE table. I dont have the means to that on the street, at least no accurately.
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Old 12-30-2007, 10:42 PM   #8
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You won't need to rescale the spark table and I don't recommending doing so until you dyno tune the car. Then when you're at the dyno, rescale a table and start from scratch so you know you aren't running too much advance.

You know what sam. Take the DIY table. Leave the N/A portion alone, don't touch any of it. Then just rescale the boosted part to your liking. It will be a win win situation for you that way.
Easy right
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Old 12-30-2007, 10:47 PM   #9
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I'm running N/A on the MSPNP... I'm scaled just as it is in the base map with the VE tuned by Jerry. I thought about scaling it for 100 and using the available resolution but the car runs great and I don't know that the effort would be worth it really.
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Old 12-30-2007, 11:45 PM   #10
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You should scale it to how much boost you are running. if you are running 10psi, no reason to scale it to 20psi. this can give you better resolution out of boost (you only need 1 row in boost really).

ftw, i run 14psi, just under 200kPa, my highest row is 212kPa for headroom. With only 4 boosted rows.
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Old 12-31-2007, 12:22 AM   #11
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I understand why you would only need 1 boosted row, it like needing only one row at WOT.

But the spark table not matching the VE table has me worried.

I think the smart approach right now, would be to continue driving like it is. Then when the turbo is installed, rescale the fuel table accordingly and tune, then follow up with a dyno tune for the spark table.
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Old 12-31-2007, 01:26 AM   #12
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sounds like a plan.
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