18psi

iTrader: (76)

He either offers awesome help or terrible help.
It's the job of the end user to differentiate.

deezums

iTrader: (3)

These are numbers, you can see how I add more fuel around 1500 rpm, then remove it after a while.

If you aren't adding fuel because you want a linear VE table you are doing it wrong. My 1.6 seems to suck the peter around low load 1500-2500, so it takes more and more fuel to make power there. If I were to try and throw the same amount of fuel at a higher map, it would flood out and choke.

So yeah, my advice is still completely ignore AE, especially if you are sequential fueling, and figure out your VE table. It may not take numbers that look pretty, and you obviously have never done this before so don't try and feed it the numbers you expect.

Don't try and let autotune tune this low load/rpm **** either, because it doesn't work.

Braineack

iTrader: (62)

looked at log, fuel map needs more fuel.


TPS still causing lean spikes since no AE.

satisfied

Wow, thank you, those do NOT look like how I expected well tuned VE to be.

Seriously I figured if the **** wasn't smooth and linear it was just plain wrong.

Why are the numbers in your VE table so high? Smaller injectors? What do the numbers represent exactly? Volumetric efficiency, but how is that quantified. Just so I can put some physical concept into this lesson, if you would be so kind.

patsmx5

iTrader: (16)

His VE is messed up, that's not normal. Around idle should be lower than that. Mine is in the low 80's/high 70's at idle for reference. His being high suggest a settting problem (AIT correction, injector dead time, voltage compensation is wrong)

deezums

iTrader: (3)

I've done bad things to input values (req fuel) to try and extract as much resolution as possible from the parameters I'm given. Basically, since my VE numbers are double my req fuel is 1/2 nominal, and one point difference in VE does not change the fueling as much, theoretically. That causes other problems I don't care to entirely explain. (It's not exactly half, that's just kinda how it works. I assure you it's nothing to do with AIT deadtime or voltage comp.)

VE is supposed to be something but it doesn't really work that way in real life, so just think of it as a number to get the pulsewidths you require. FWIW, I think you need to "incorperate afr target" to get a "true" VE table, but I never looked into it. You should also ditch the thought that your VE values should match someone else's, because that's a very very bad line of thought IMO.

If you really want to know, read all this. Your VE table will be even more useless if you switch to incorporate now, so now would be the time to decide.

How MegaSquirt(R) EFI Controllers Work

patsmx5

iTrader: (16)

Req fuel gets used in other calculations besides just fueling based on VE. That's why your car runs weird. Fix your req fuel.

deezums

iTrader: (3)

Pat, no, please stop. I guarantee you've no idea what's going on in my MS2, that I know what's happening with fuel comps, and I promise my car runs better than yours on less ECU.

patsmx5

iTrader: (16)

I used to run MS2, it's a good ecu. But didn't you just post, today, that your car stalls out under certain conditions? And that it does so when warming up?

Mine doesn't have any of these problems, but like you said, I'm sure you know more about it than I do and your car runs better.

deezums

iTrader: (3)

I posted saying my car stalls once, on the very first cold start of the day. I then said I had my closed loop idle so flawless that you could never stall it once it's at temperature. I run e85. Cold start.

I don't know why you think my tune is fucked, but I assure you it isn't. You read something that wasn't there again, I'm trying my best to not confuse this guy harder and you aren't helping.

patsmx5

iTrader: (16)

If you have VVT, then when the VVT makes large swings, your VE does too and your table will reflect this. On my setup I go full advance around 2,000 RPMs on the VVT, so that does cause the VE to have a steep climb there for example.

patsmx5

iTrader: (16)

I too run E85, I feel your pain there.

Sounds like you know about tuning than I do.

OP asked why your table is so high, I said that ain't normal, cause it's not. You explained why (cause your req fuel is off).

Braineack

iTrader: (62)

it all depends.

a fuel map is going to look much different than a VE map.

this depends on a setting for the fueling algorithm.

deezums

iTrader: (3)

I do not include AFR target, so my VE table is not a VE table and is just a fuel map.

My megasquirt only uses the AFR table for autotune and O2 correction, nothing more. It also has a lot less resolution than the VE table which is my reason for not using it. If I make changes to the AFR ratios I would like to run, I just rerun autotune.

Theoretically you could incorporate AFR target and change just the AFR table to get different final pulsewidths, but I imagine you'd still need to autotune a slight bit anyway and you'd restrain yourself to 12x12 instead of 16x16. There's no real advantage then, not as far as I can tell. If you got to changing timing with AFR it would be even more pointless.

Braineack

iTrader: (62)

looks much different than any others i've seen. but like I said, if it works, then whateverzzzzzzzzz

mine typically look like this--getting a little fatter where you're getting leaner:

deezums

iTrader: (3)

I don't know how you compare this to that, the scale is all different. If you topped off at 200kpa, how different would the really look?

His car seems to want more fuel around 1500 rpm, much like the bump in my fuel map.

His map looks like yours now, it idles fine but will be lean as potatoes 4 cells to the right, if I'm not mistaken. It needs to look more like mine, bump in fuel that tapers out before peak power, then back to normal looking table.

Mine is tuned like **** under the boost over 4.5k or so, I've just interpolated stuff over. I can't hit those cells, or I don't very often.

satisfied

My tables 3d looks surprisingly very similar to brains. I'm going to take all this to heart, reread the thread, workout, and tune. As well as accept pats offer to take a look at my tune. I really appreciate the education guys. I really want to get this down.

patsmx5

iTrader: (16)

This is very close to what my VE table looks like in shape. My high VE numbers don't climb as high in the upper right corner, but the shape across the map is practically the same.

Braineack

iTrader: (62)

That's mainly for safety since it's a basemap table. I usually see fuel in boost stay flat from peak boost till redline.

patsmx5

iTrader: (16)

Ah, makes sense. On my setup the high VE rows are in the 130's around 250kPa. But that's supercharged, not turbo. Also I need more timing up top, I think that's going to change those cells, previous testing shows adding even 1* of timing causing AFRs to lean out, requiring more fuel. Will be interesting to see where I end up once I get the spark tuned for E85, might be closer to what you show in the midrange at full boost.