PowerFC: Some DIY tuning comments please

[89CAL]

I don't have a wideband yet but I will be getting an AEM Uego unit hopefully tomorrow if this guy answers his phone!

I'm close to the money on the settings as it seems, maybe ill give it +14ms and tune from there.

At the moment, I am not doing anything fancy, just sorting out the pops and splutters on idle and cruising, so ill be adding more fuel rather than pulling which should be safe to do without a wideband. I just listen to it and when the pops are gone I know I'm done lol.

Quite interesting this tuning stuff.

I wouldn't touch your injector settings till you have a wideband installed

[SargeRX8]

I was just having a read around and from what Ive read it seems that injector settings are just a correction to compensate for the changed injectors, an easy fix so to speak. If you are going to tune the car from scratch, for example, after you init the power fc, could you use those standard settings of 100% 0ms to tune the car to the correct afr? Technically this should work as the car will be tuned around the injectors on that setting. I don't see it not working like this.

The correction is just the easy way out for when you have a tune and then don't want to retune because of injectors, just get the correct settings and bam. But if you start from a clean slate at 100% and fix setup the AFR's in the injector map, it should be fine. Right?

[The Mafia]

Unfortunately you can only go to a max of 1.5 and min of 0.5, so apologies but that idea goes right out the window.

Don't be lazy, correct your injectors.

Also, the map doesn't scale exactly how you're hoping.

[SargeRX8]

Its not about being lazy really lol, I know the settings for my Nismo injectors 50 and 14ms but just wanted to ask as I read in a different thread that you can leave it at 100% 0ms and tune the car based on that.

This scaling shit is weird to me. There are many places which can affect scaling. Example, my % for my AFM aren't at 100%. Each voltage gets a lower %. At 0.64 its 100%, the next one is 96 next one 95 then eventually 85. I don't know why it is like this(They are all 100% by default) but that is how it got tuned for $800 so there must be a reason behind it.

Also I done an init on my ECU, let it self learn the idle(after setting the AFM and injectors settings) and it started and idled just fine. I went to copy my old map across and now it feels the same again. Weird shit.

[89CAL]

If you copied your old map across it probably copied your old injector settings also or did you correct them again?

[SargeRX8]

I corrected my injector settings. Only thing that would have changed is the AFM voltage settings thing. All the boxes after the init were 100%, on my tune they taper down to 85%. I am using the settings which my car was tuned on, 52 10ms but I am aware that the nismo are 50 14 but as it was tuned, it how it will stay. Before I fiddle further I will do a compression test when my coils arrive and new plugs get dropped in.

[DVS JEZ]

Some tuners tune by afm correction obviously advan is one of them. If i did notice that i would have set to 100% and tune like i normally do.

I think u should start from an init and leave the afm at 100% and tune it

[SargeRX8]

Some tuners tune by afm correction obviously advan is one of them. If i did notice that i would have set to 100% and tune like i normally do.

I think u should start from an init and leave the afm at 100% and tune it

When the car is ready, I'll leave that up to you lol. I'm just tinkering with low tiny load and idle.

[STATUS]

Its not about being lazy really lol, I know the settings for my Nismo injectors 50 and 14ms but just wanted to ask as I read in a different thread that you can leave it at 100% 0ms and tune the car based on that.

This scaling shit is weird to me. There are many places which can affect scaling. Example, my % for my AFM aren't at 100%. Each voltage gets a lower %. At 0.64 its 100%, the next one is 96 next one 95 then eventually 85. I don't know why it is like this(They are all 100% by default) but that is how it got tuned for $800 so there must be a reason behind it.

Also I done an init on my ECU, let it self learn the idle(after setting the AFM and injectors settings) and it started and idled just fine. I went to copy my old map across and now it feels the same again. Weird shit.

unfortunately your accel pulse, crank pulse and everything that requires accurate injector pulse timing will be up the creek, yes you could do it but every single fueling curve would need changing and it would still be behid the eight ball when finished. The PFC has a lot of areas that are non adjustable in the back ground which rely on the lag time and % correction to bring it back into check.

[STATUS]

I corrected my injector settings. Only thing that would have changed is the AFM voltage settings thing. All the boxes after the init were 100%, on my tune they taper down to 85%. I am using the settings which my car was tuned on, 52 10ms but I am aware that the nismo are 50 14 but as it was tuned, it how it will stay. Before I fiddle further I will do a compression test when my coils arrive and new plugs get dropped in.

Tuning in the AFM percentage table is a sign of pure laziness, poor form unfortunately. I like the write my fuel map so that it accuratley resembles my target lamba / AFR i then re write the AFM table to get my results. This means its easy to make correction in the future as inputing the desired afr in the fuel table means you will get the same result out the tailpipe. Especially handy with fuel changes or a trip to the drags or a turbo swap etc.

Tao from hypergears fuel and afm curve is so close to being perfect we can swap between different size turbos and the tune requires only 1-2 pulls to be spot on the target AF in the fuel table. Timing is still a dynamic thing.

[The Mafia]

Thanks status, you've saved me a lot of typing.

To everyone else - STATUS could not be any closer to the truth. He's right on the mark.

[urtwhistle]

ahhh very interesting, that explains alot. I never really understood fully why the air flow curve was not a linear relationship, ie airflow to voltate. But now it makes a little more sense.

Trent, what is the best way to actually setup an airflow curve. do you set the fuel map to represent the target AFR first, then slowly tweak the corresponding Air flow load points. until the target afr matchs the actual afr?

regards

Chris

[SargeRX8]

What exactly do you mean when I write that. Do you mean that you initially leave your curve at 100% across the board then setup the injector table to reflect the afr you want. Meaning if you wanted the whole map to be stoich, 14.7, you would set that on the whole map then adjust the air flow to get 14.7 out the rear?

[STATUS]

ahhh very interesting, that explains alot. I never really understood fully why the air flow curve was not a linear relationship, ie airflow to voltate. But now it makes a little more sense.

Trent, what is the best way to actually setup an airflow curve. do you set the fuel map to represent the target AFR first, then slowly tweak the corresponding Air flow load points. until the target afr matchs the actual afr?

regards

Chris

Bingo. Just make sure you do it smoothly, no big jumps that way all load points regardless of boost match your desired afr in the fuel table.

[STATUS]

What exactly do you mean when I write that. Do you mean that you initially leave your curve at 100% across the board then setup the injector table to reflect the afr you want.

yes the table with percentages should always stay 100%, use the table below it to fine tune.

Meaning if you wanted the whole map to be stoich, 14.7, you would set that on the whole map then adjust the air flow to get 14.7 out the rear?

Exactly, but 14.7 would be difficult on a turbo car.

[SargeRX8]

yes the table with percentages should always stay 100%, use the table below it to fine tune.

Exactly, but 14.7 would be difficult on a turbo car.

Yeah, just for example lol.

That is very interesting but it seems like a harder way to tune. It would be easier in my mind, or the mind of a novice, to leave those as standard and adjust the fuel injection as necessary across the load points.

Ive sent you a PM. I actually didn't it wouldn't let me...

Edited November 8, 2011 by SargeRX8

[urtwhistle]

Does any 1 want to share there Inj map so that I can have a quick gander at what they used as a target AFR's across the board?

Would I be correct in saying that every car would need a slightly different airflow curve?But for the most part the target afr or inj map would stay pretty much the same. For example my car is a neo RB3025 with a GT3576 and z32 AFM. it would have a different airflow requirements to a RB25 with a GT3576 and z32 AFM due to the extra capacity. But the fuel map would be quite similar.

I obviously did it the other way by using the standard airflow curve and tuning the inj map to compensate. So once I get the idea through my head of how it works, I might start slightly tweaking it via the airflow curve.

regards

Chris

[urtwhistle]

Does any 1 want to share there Inj map so that I can have a quick gander at what they used as a target AFR's across the board?

Would I be correct in saying that every car would need a slightly different airflow curve?But for the most part the target afr or inj map would stay pretty much the same. For example my car is a neo RB3025 with a GT3576 and z32 AFM. it would have a different airflow requirements to a RB25 with a GT3576 and z32 AFM due to the extra capacity. But the fuel map would be quite similar.

I obviously did it the other way by using the standard airflow curve and tuning the inj map to compensate. So once I get the idea through my head of how it works, I might start slightly tweaking it via the airflow curve.

regards

Chris

[STATUS]

Yeah, just for example lol.

That is very interesting but it seems like a harder way to tune. It would be easier in my mind, or the mind of a novice, to leave those as standard and adjust the fuel injection as necessary across the load points.

Ive sent you a PM. I actually didn't it wouldn't let me...

you would be suprised it actually is the same time wise and if you use the numbers enough (like evryday like we do) then you can nearly write the map without a dyno.

[SargeRX8]

you would be suprised it actually is the same time wise and if you use the numbers enough (like evryday like we do) then you can nearly write the map without a dyno.

If I send you my tune can you have a look at it and if possible make any suitable adjustments? I am happy to $ for your work if you believe you can make a difference. It seems sloppy in the lower range. If you are able to, PM me.