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19 minutes ago, Dose Pipe Sutututu said:

If you're using an Elite, disable the transient fuel function and use the MAP prediction. It's light years ahead of the transient crap.

The MAP prediction setup looks complex to me, i don't understand any of the 4 pages really 🤷🏻‍♂️. I'll have to do some research
 

Also, from your experience, should i be afraid of using the LTFT as a means to improve drivability over time? 
 

Edited by ChrisW434
3 minutes ago, ChrisW434 said:

From your experience, should i be afraid of using the LTFT as a means to improve drivability over time? 

 

Not at all, it's there for a reason. Both ST and LT fuel trims are there to be used.

Think of a modern EFI stock car, they utilise both ST and LT as well.

Of course you want to have the injector data, coolant temp, fuel temp, fuel density, baro, air temp tables all correctly defined with fuel trims against them so your LT and ST aren't working hard to meet the AFR targets.

You'll also find that with bigger cams, you might need to target a bit richer than stoich as you'll find it will buckle.

I'll send some screen shots of how I set things up (once Lenovo the pricks send back my laptop, been 3x weeks to replace a mobo under warranty).

8 minutes ago, ChrisW434 said:

Righto, i'll have look into that now. I have the laptop with me, but not the car. 
 

From your experience, should i be afraid of using the LTFT as a means to improve drivability over time? 
 

LTFT is a useful tool, but always ask yourself why it's correcting first (I.E is it being too aggressive? is it fighting with decel?). Also more importantly, manually smooth out your fuel map afterwards as it will make it ugly and lumpy after applying. 

Edited by TurboTapin
5 minutes ago, Dose Pipe Sutututu said:

Not at all, it's there for a reason. Both ST and LT fuel trims are there to be used.

Think of a modern EFI stock car, they utilise both ST and LT as well.

Of course you want to have the injector data, coolant temp, fuel temp, fuel density, baro, air temp tables all correctly defined with fuel trims against them so your LT and ST aren't working hard to meet the AFR targets.

You'll also find that with bigger cams, you might need to target a bit richer than stoich as you'll find it will buckle.

I'll send some screen shots of how I set things up (once Lenovo the pricks send back my laptop, been 3x weeks to replace a mobo under warranty).

All sounds good, thanks for that. I'm not starting from scratch as the car is tuned prob 95% just trying to clean up drivability myself as it's obviously really expensive to keep paying a tuner for diminishing returns. The fuel tables are set up decent, as is the basic setup.. i think

I mean ideally trims are there because base tables are never 100% accurate. You want them to be as accurate as you can possibly get them, but temperature variations, different altitude, heat, everything likes to mess with how accurate a base table can be.

Fuel trims and Narrowband/Wideband fuel control exist to realistically fill this gap/fuzzy factor, and do their job great. But while they will drag your AFR/Lambda to a target, you want them to have to do as little work as possible.

Don't tweak any of this stuff without a wideband. Unless it's something like "Disable 'Ghost Cam' because it's very obvious when looking into the Tune", you are guessing with regards to your AFR.

You are absolutely right and it's far better to spend the money on a Wideband controller (especially with haltech) and the fab to get it plumbed in NOT where the narrowbands sit (it is supposed to be 1 meter from the turbo), and teach yourself all this little finicky stuff. This is stuff no tuner can ever really be expected to get perfect, but the owner of the car will see SO much livability improvements by learning and tweaking these things - With the proper tools.

It IS the difference between "Oh yeah my tuned car drives a bit like a tuned car" and "My car drives like a factory car"

It does take a lot of time and tweaking and fun, but you'd never want to be paying $150 an hour for someone else to spend that much time on it.

@ChrisW434

If tuning is new to you, this might be really useful - 

https://evansperformanceacademy.vhx.tv/

They run a subscription model, so for $50 USD you get access to 100% of the content. Turn it on, watch like crazy for a month and turn it off. The value is crazy. 

This is how I learnt to tune many years ago. Since then, I go back to the site every couple of years to catch up on new content. I wish HPA ran the same pricing, they are so expensive in comparison lol. 

10 hours ago, Kinkstaah said:

I mean ideally trims are there because base tables are never 100% accurate. You want them to be as accurate as you can possibly get them, but temperature variations, different altitude, heat, everything likes to mess with how accurate a base table can be.

Fuel trims and Narrowband/Wideband fuel control exist to realistically fill this gap/fuzzy factor, and do their job great. But while they will drag your AFR/Lambda to a target, you want them to have to do as little work as possible.

Don't tweak any of this stuff without a wideband. Unless it's something like "Disable 'Ghost Cam' because it's very obvious when looking into the Tune", you are guessing with regards to your AFR.

You are absolutely right and it's far better to spend the money on a Wideband controller (especially with haltech) and the fab to get it plumbed in NOT where the narrowbands sit (it is supposed to be 1 meter from the turbo), and teach yourself all this little finicky stuff. This is stuff no tuner can ever really be expected to get perfect, but the owner of the car will see SO much livability improvements by learning and tweaking these things - With the proper tools.

It IS the difference between "Oh yeah my tuned car drives a bit like a tuned car" and "My car drives like a factory car"

It does take a lot of time and tweaking and fun, but you'd never want to be paying $150 an hour for someone else to spend that much time on it.

Love that info, agree with all of it. I have a WB1 controller for it, and i welded the bung around a metre from the turbo down near the transmission. Seems to work well and should not get baked too quickly...

I'm happy to hear others acknowledge the whole "drives like a tuned car" deal as i was initially disappointed after the first couple tunes, but have since learnt the reality. I can only imagine how many hours would be in a factory ecm to get a factory car driving like they do!

Keen to get the LTFTs up and running and maybe i'll see a little improvement over time 👍🏻

9 hours ago, Murray_Calavera said:

@ChrisW434

If tuning is new to you, this might be really useful - 

https://evansperformanceacademy.vhx.tv/

They run a subscription model, so for $50 USD you get access to 100% of the content. Turn it on, watch like crazy for a month and turn it off. The value is crazy. 

This is how I learnt to tune many years ago. Since then, I go back to the site every couple of years to catch up on new content. I wish HPA ran the same pricing, they are so expensive in comparison lol. 

I have watched a couple of Evans demos on youtube. Pretty good hey. I was considering it, as it looked awesome. Good feedback about it is encouraging so i might subscribe to learn more and get this 90s JDM nugget sorted

  • Like 1
8 hours ago, R32RB20 said:

Hey @ChrisW434 did you end up changing the decel fuel cut? did it work? make sure you post what worked for you, it may help other currently or in the future :)

Hi,

i did try turning off the decel fuel cut, and noticed a positive change when on/off throttle in traffic, but needs tweaking as the car runs on more than i'd like.

So thats still in progress.

Also, i richened up the fuel map slightly and  gave it more ignition advance to smooth out the idle which also helped.

I've got some good advice to follow with other settings also so theres more to do.

👍🏻

  • Thanks 1

Got my laptop back after 3x fking weeks at Lenovo... pricks.

Anyhow, here are some screenshots of my tune and how I've calibrated my shit box.

This is the best thing to come out on the Haltech since sliced bread:

image.thumb.png.876b4e6585c41ab59c634106ca192035.png

 

If you make all this say 15 instead of 12 or whatever so there's not a big timing jump between 950 to 1000 the idle won't "brap" as much. I did this because I am a poser

image.thumb.png.4f8d23eae9043d9b454f7f560a9a1acc.png

 

Decel, I find adding in heaps of fuel on recovery stops the idle being aids

image.thumb.png.0e726cc0a9205279a8d035061f9ac103.png

 

Also defining fuel density vs. ethanol percentage vs. fuel temperature immensely improved the car's driveability 

image.thumb.png.12cb80ac5fbed204ae8d8f441e6d4b2e.png

 

3 hours ago, Dose Pipe Sutututu said:

Got my laptop back after 3x fking weeks at Lenovo... pricks.

Anyhow, here are some screenshots of my tune and how I've calibrated my shit box.

This is the best thing to come out on the Haltech since sliced bread:

image.thumb.png.876b4e6585c41ab59c634106ca192035.png

 

If you make all this say 15 instead of 12 or whatever so there's not a big timing jump between 950 to 1000 the idle won't "brap" as much. I did this because I am a poser

image.thumb.png.4f8d23eae9043d9b454f7f560a9a1acc.png

 

Decel, I find adding in heaps of fuel on recovery stops the idle being aids

image.thumb.png.0e726cc0a9205279a8d035061f9ac103.png

 

Also defining fuel density vs. ethanol percentage vs. fuel temperature immensely improved the car's driveability 

image.thumb.png.12cb80ac5fbed204ae8d8f441e6d4b2e.png

 

 

Thanks heaps, gonna dive in and look at all this awesome info! 
i'll reply once i've look at all this goodness...

  • Like 1
3 hours ago, Dose Pipe Sutututu said:

Got my laptop back after 3x fking weeks at Lenovo... pricks.

Anyhow, here are some screenshots of my tune and how I've calibrated my shit box.

This is the best thing to come out on the Haltech since sliced bread:

image.thumb.png.876b4e6585c41ab59c634106ca192035.png

 

If you make all this say 15 instead of 12 or whatever so there's not a big timing jump between 950 to 1000 the idle won't "brap" as much. I did this because I am a poser

image.thumb.png.4f8d23eae9043d9b454f7f560a9a1acc.png

 

Decel, I find adding in heaps of fuel on recovery stops the idle being aids

image.thumb.png.0e726cc0a9205279a8d035061f9ac103.png

 

Also defining fuel density vs. ethanol percentage vs. fuel temperature immensely improved the car's driveability 

image.thumb.png.12cb80ac5fbed204ae8d8f441e6d4b2e.png

 

 

Righto: 

pic 1: awesome, and i've found Haltech has good info about this so its cool to see a working example.

pic 2: looks like my current one lol. I'll smooth it out whilst i sort the driveability. The brappy idle is a guilty pleasure though haha.

pic 3: I'll compare that to mine and see how that goes. Looks good.

pic 4: this table has similar numbers in the cells, so i'm guessing this one is quite sensitive to values?

1 hour ago, ChrisW434 said:

this table has similar numbers in the cells, so i'm guessing this one is quite sensitive to values?

It's just fuel density vs. temperature. I got that data from BP Australia and then interpolate it with E85 data 

5 minutes ago, Dose Pipe Sutututu said:

It's just fuel density vs. temperature. I got that data from BP Australia and then interpolate it with E85 data 

Thats pretty switched-on 👌🏻
 

i'm keen to see how the predicted MAP table updates and changes as it gets driven, as the initial generic figures are much different to your displayed ones.

Edited by ChrisW434
  • Like 1
Just now, ChrisW434 said:

Thats pretty switched-on 👌🏻

Whatever it takes to make it drive like a M2/3/4 lol.. (on going joke here with me).

Nek minnit in goes a BMW DCT or ZF box 

1 minute ago, Dose Pipe Sutututu said:

Whatever it takes to make it drive like a M2/3/4 lol.. (on going joke here with me).

Nek minnit in goes a BMW DCT or ZF box 

Ha, i'm super fussy with driveability, and it burns that my money pit drives like a "tuned car"

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