VE table values greater than 1.0

A1C calibration can be modified and configured to operate all EFI-SD4x ECUs in 4 cylinder, 6 cylinder and 8 cylinder configurations.
Sevensecondsuv
Posts: 137
Joined: 2021 Nov 08, 22:24
Location: North Central IL
Vehicle Information: 1995 F-250 RCLB with a built 300 and 4-spd running A1C
wbo2_aem_uego

VE table values greater than 1.0

Unread post by Sevensecondsuv »

Hi all. I'm still working with the tune Michael started for me. In an effort to get the idle to behave, he adjusted injector offset and slope. I'm now working on dialing in fuel. I've got the VE table cells for high rpm and load at 99.90 and some still need another 15% fuel. I'm wondering what will happen if I put a value greater than 100 in those cells? Will that work or is the ECU not capable of reading values greater than 100?

Yes, I realize the better answer is adjust injector slope, but this is the first tune I've worked with that is actually pretty driveable since starting this process 2 years ago. So I'd like to just get the fuel dialed in and actually get some use out of the truck.

I suspect the issues with the earlier tune attempts were the old XDFs and the fuel transient scalar that efloth also had issues with. But again, I'm close enough now and really ready to be done with this thing.
efloth
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Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: VE table values greater than 1.0

Unread post by efloth »

I find it easier to dial in the ve table in hex view.(Right click on the table and click show raw values) You can also set a cell to ff and then switch back to calculated view to find the maximum value in decimal.
decipha
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'25 F-150 5L

Re: VE table values greater than 1.0

Unread post by decipha »

you can plug in all the way to 200

why would you use hex view? Why does the value itself even make any difference?

All I do is multiply each cell by the correction the histogram gives you. Then I make sure they are all in linear order and if not adjust the injector data to make it.

I've broken out a significant amount of A1C in the past couple months alone. Post your current tune and log in your thread and I'll take it from there.
efloth
Posts: 399
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: VE table values greater than 1.0

Unread post by efloth »

I use hex so I can control rounding up or down. Splitting hairs probably. But easier to control exactly what is happening.
decipha
Posts: 6384
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Vehicle Information: Work Truck
'25 F-150 5L

Re: VE table values greater than 1.0

Unread post by decipha »

How much percentage difference would that make? Should be less than half a percent.

That amount of percentage is pretty negligible.
Sevensecondsuv
Posts: 137
Joined: 2021 Nov 08, 22:24
Location: North Central IL
Vehicle Information: 1995 F-250 RCLB with a built 300 and 4-spd running A1C
wbo2_aem_uego

Re: VE table values greater than 1.0

Unread post by Sevensecondsuv »

Thanks Michael and Efloth. I posted the files in my premium thread.
Sevensecondsuv
Posts: 137
Joined: 2021 Nov 08, 22:24
Location: North Central IL
Vehicle Information: 1995 F-250 RCLB with a built 300 and 4-spd running A1C
wbo2_aem_uego

Re: VE table values greater than 1.0

Unread post by Sevensecondsuv »

If I put a value greater than 100 in the table and save it, it cuts it down to 99.61 when I reopen the table. Is there a limit I need to adjust in the XDF?

Update:
When I view in hex, the 99.61 value is FF, so apparently that's the max it'll accept without more bits per cell. I see the underlying formula is cell value / 256, so somehow 100 is getting converted to 255 in hex. I suspect this could be solved by using fewer decimal places, but I'm not smart enough with the coding to figure out what to change in the xdf.

I do see there's a scalar for global VE table multiplier that'll go up to 2.000. Will that function with the expanded VE table patch? I think I'll try setting that to 2.0, multiply all the cells in the VE table by 0.5, and that should allow me more room to increase VE in the areas of the table where I need it.
decipha
Posts: 6384
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'25 F-150 5L

Re: VE table values greater than 1.0

Unread post by decipha »

You dont have the ve multiplier set to 2

correct
Sevensecondsuv
Posts: 137
Joined: 2021 Nov 08, 22:24
Location: North Central IL
Vehicle Information: 1995 F-250 RCLB with a built 300 and 4-spd running A1C
wbo2_aem_uego

Re: VE table values greater than 1.0

Unread post by Sevensecondsuv »

Now I see the expanded VE table patch was not patched in that bin, so perhaps I was changing values in the wrong table. Next I'll try modifying the original size VE table. That one still has some margin to 100%.

If that doesn't work I'll enable the patch and go back to working on the expanded table.
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