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GLF by numbers: A Dave_Q and 320touring production


Dave_Q

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Howdy shitters, I felt like doing a car related post to take my mind off the shocking lack of progress on actually doing anything to my chod recently.

My mind is full of all sorts of shite, some useful, some not. 

Included in this is a pretty good understanding of how more primitive diesel engine management systems work, and how to suck out the digital nectar, make the numbers bigger and put it back for some GLF.

So in this thread I will attempt to lay out some of this in a way that will make it possible for others to follow. 

 

1. DIS SHIT IS DANGEROUS YO. I mean, probably not really, but what I'm saying is that there is a small risk of turning your car's brain into a permanent vegetable and I will not be held responsible, obvs.

2. The how to bit is primarily aimed at VAG TDIs in VE pump and PD FLAVA. This is because the map editing is well catered for with an excellently written and fairly easy to use freeware program. If you're keen to do something similar with another type of engine I can try and help, but finding the maps etc is a lot more work. 

3. Do not EVER flash a file off the internet onto your car if you'd like to use it again. Get your original file, save it somewhere safe and make modifications to your original file and flash that - small differences in software or hardware versions can lead to the consequences in point 1.

I'll "reserve" the next 2 or 3 posts and edit them as and when I get a chance to include the following:

Theory - how your ECU decides how much to squirt and when

Reading and writing - recommended tools for how to read your car's brain

Modding - a quick guide to doing a "Stage 1" type map on a suitably shitey engine like a 90hp TDI with veg-tastic VE pump.

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So, how does your ECU decide how much fuel to chuck in?

This example is based on a PD100 TDI but most of the maps are the same across all VE and PD TDIs.

So firstly, we have a loud pedal. This is pretty much a variable resistor that gives a voltage signal to the ECU that is interpreted as 0-100%.

This goes into our first map, called Driver's wish.

post-17573-0-01256700-1496695524_thumb.jpg

Now the majority of these maps are 3D, which means that the ECU references 2 values to give a 3rd.

For example, here the throttle position and engine rpm are cross referenced to give an amount of fuel, referred to in units of mg per cycle.

This table version may (or may not) help with the visualisation.

post-17573-0-96373200-1496695673_thumb.jpg

So let's say we've got our foot flat to the floor, and the engine is doing 2500rpm - the ECU decides that means we want 50mg/stroke.

Next, some other things happen. I'm not 100% on the order -they may all happen at the same time.

First (possibly), our ECU has a think about how much air it might need to burn 50mg/stroke of fuel. It looks this up on a boost map.

post-17573-0-07248700-1496695927_thumb.jpg

post-17573-0-41538400-1496695928_thumb.jpg

This looks at requested fuel vs rpm and decides what turbo boost to aim for. Note that the highest value on the fuel axis is 45mg, we're asking for 50mg. The ECU will use the value from the 45mg column - 45mg at 2500rpm is 1980millbar - this is given in absolute intake manifold pressure so works out at 0.98 bar or about 14psi of boost. The ECU will therefore command a valve or something (VG turbine here) to aim for this level of boost.

So now we chuck in 50mg of fuel into each cylinder? Not quite. We check against a couple of limiters to see if it's safe and wise to do so.

Firstly, the torque limiter. This is another 3D map, with 3 rows of values with maximum fuel quantity by rpm - this is basically to protect the gearbox and clutch and promote reliability. Interestingly (to me anyway) this map can be used to derate maximum power at altitude by decreasing the maximum IQ at lower atmospheric pressure, but I've never seen one with any different values here at the different pressures.

post-17573-0-57502100-1496696379_thumb.jpg

post-17573-0-54312300-1496696380_thumb.jpg

So we're not injecting 50mg anymore, our limit at 2500rpm is 44.2mg.

So inject 44.2mg now yes?

No. One more check which is to see if we've got enough air to burn it all without a load of clag - the smoke limiter.

post-17573-0-54431500-1496696551_thumb.jpg

post-17573-0-87863800-1496696552_thumb.jpg

Units here are intake air (measured by the MAF, in mg/stroke) vs rpm. Let's say our MAF tells us we only have 750mg or air per cylinder, therefore we're now injecting 38.5mg of fuel per cylinder.

That's pretty much it for the logic of how the fuel quantity is decided. Now we have that we need to open an injector or 4.

post-17573-0-55718400-1496696852_thumb.jpg

post-17573-0-37508300-1496696854_thumb.jpg

Here the table is in units of mg/stroke vs rpm, and for 38.5mg of fuel at 2500rpm we would open the injector for something around 16 degrees of crank rotation (as the required value is in between rows, the ECU will interpolate.)

So these are the basic maps that control fuelling and boost. There are others such as EGR, various limiters and things to tell us when things are going bad, but these maps (except duration) are the ones we will mess about with later to remap the car.

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Reading and writing.

There are 2 main interfaces for reading over OBD.

MPPS and Galletto.

MPPS is recommended as it can do some recovery of failed flashes.

Both of those links are to ebay clone versions of pro tools that cost many money, obviously they're based on simple serial chips and provided with copied software but do work alright in my experience. 

I would also recommend getting a VCDS/VAGCOM cable, the <£5 blue one from ebay is fine and can be used for datalogging and fault finding.

The software is pretty self explanatory, although I may see if 320touring will do us a quick how to video, will add it here if he does. 

When reading or writing the ECU you should make sure that there is no chance your laptop or car battery will run out. It's recommended to have the laptop plugged in and the car on a charger (I never bother, but at least make sure your laptop has a fully charged non-dodgy battery.)

As we're talking about VAG cars here is some further info on what can and can't be mapped over OBD.

Very early TDI such as 1Z, early AHU, early AFN (pre 98 or so)

These have a management system called MSA15. These cannot be mapped over OBD. To remap these you need to desolder the chips from the ECU main board and solder in sockets, read the chips in a programmer and write your map to a new one.

The ECU looks like this.

post-17573-0-98262200-1496872052_thumb.jpg

Very early ones (mostly 1Z) have a black plastic case but look the same.

Most VE pump TDIs from 98 or so on will have the EDC 15 ECU which looks like this.

post-17573-0-55795900-1496872077_thumb.jpg

These can be read and written over OBD.

All PD engines should be able to be read no problem.

Newer CR tdi stuff isn't covered here - these are newer management systems eg EDC16, EDC17 - they should be able to be read / written using the same tools, but the newer they are the more maps and limiters are involved, so my how to bit will focus on EDC15.

If anyone wants to order themselves a wire go ahead, I'll write up the remapping bit maybe over the weekend.

If you have any questions on your particular car or anything else, fire away.

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Modding - what to do with your file once you have it.

BIG SHOUTY CAPITAL WARNING - SAVE YOUR ORIGINAL FILE IN MULTIPLE SECURE LOCATIONS IN CASE YOU FUCK THINGS UP AND NEED TO GO BACK TO STOCK.

The program you need is available from this site, the one you need is called VAG suite. 

Install it on your computer. It is free, safe to use software put together by a top level diesel nerd / enthusiast by the internet name of Dilemma. 

I will be using a map from a PD100 Fabia as I have one on my computer - I will note where it differs for VE pump engines.

Once you have it, use it to open the file you read from your computer.

That will give you a screen like this.

 post-17573-0-66793700-1497038436_thumb.jpg

The software will find all the necessary maps and list them on the left. Note that all of them are there twice. 

This is because the ECU contains 2 (or more) sets of code so the same ECU can be used for different variants. In this case the 2 maps are manual and auto transmission.

I recommend changing both of each map.

So lets start at the start, the Driver's wish map. Double click on this and you will get a window showing it in graph and table view. 

post-17573-0-16778600-1497038778_thumb.jpg

This shows us that just off idle we are asking for 58mg of fuel, this decreases as the engine speed goes up. Rather than whack this up to a millionty we will find out what the ECU is calibrated for. 

On the PD this is shown on the Duration map. There are actually 5 duration maps which are used with different amounts of advance. Map 0 and map 5 are for very high and low amounts of timing advance and only go up to 30mg of fuel. 

Most of the normal operation of the engine is covered by maps 2-4, and they all have 60mg of fuel as the highest value in the fuel axis. 

post-17573-0-78655600-1497039171_thumb.jpg

If you are working on a file from a VE pump car, then instead of a duration map you will have a pump voltage map. 

This converts the requested fuel into a voltage to apply to the quantity adjuster on the pump.

This example is from a 90hp TDI and the highest column in the fuel axis is 51mg.

post-17573-0-61564300-1497039526_thumb.png

Worth noting here that it is possible to change axis values to try and get more fuel in, however this is outside the scope of a stage 1 tune.

Remember in the logic example we only ended up injecting 30-odd mg with our foot on the floor, so if we can actually inject 51 or 60mg we will get a healthy power increase.

Time to start changing maps then.

In the driver's wish map we wont change the top row (5355rpm) or the bottom couple of rows (<840rpm) as these are part of controlling anti-stall and rev limiting.

There are various ways to change the values. 

You can click on a single cell, delete the value and type in a new one.

You can highlight a number of cells and use the fill function at the top to paste in the same value to them. 

Here I'm pasting 60mg in most of the right column (100% throttle) - press the lightning symbol to do the action in the box.

post-17573-0-89977500-1497040060_thumb.jpg

This means we will be requesting 60mg at 100% throttle through most of the rev range. It does leave the map looking slightly lumpy though.

post-17573-0-68911200-1497040061_thumb.jpg

Next I just try and smooth it out a bit - first by highlighting part of the next row down and using the multiply function to multiply by 1.05 (aka increase by 5%).

post-17573-0-38673000-1497040062_thumb.jpg

I also edit the rogue 58mg at 75% throttle and 5355rpm because it doesn't follow the general trend.

The final map looks something like this.

post-17573-0-85035000-1497040063_thumb.jpg

After changing each map click save and close the window.

Remember to do the same to both versions.

Next: MOAR BOOST - sponsored by 320touring.

This map is in fuel request vs rpm - at lower fuel amounts the stock boost is probably already giving enough air to burn the fuel that you have.

post-17573-0-55719100-1497040940_thumb.jpg

The highest value in the map is something like 2050mbar (about 1.05 bar boost) - on a stock turbo you can take this to between about 2250mbar and 2400mbar depending on your level of caution. 

What I do is highlight the last 2 columns and use multiply by 1.05 a couple of times until the peak value gets to about 2250, and the shape is kept. 

This is my finished map.

post-17573-0-21292300-1497040939_thumb.jpg

This is, genuinely, 320touring's "drag spec" map from his Fabia.

post-17573-0-52368200-1497040937_thumb.jpg

You can make your own mind up as to the best approach. :D

 

We need to adjust some limiters so our improved boost doesn't give fault codes or put us in limp mode. 

Firstly the boost limit map:

post-17573-0-79358900-1497041206_thumb.jpg

Secondly the SVBL (single value boost limit)

post-17573-0-21359900-1497041207_thumb.jpg

Both need to be about 100mbar higher than your target. Obviously you could set them significantly higher but then you would lose out on a failsafe against overboost.

Finally we need to change the fuelling limiters to make sure we actually get something closer to the amount we are requesting. 

Torque limiter first - I suggest going easy below about 2250rpm if you like your clutch. Here I have filled from 2250rpm to about 3800rpm with 60mg, and smoothed out the map around 1800-2250rpm.

Stock:

post-17573-0-48903300-1497041611_thumb.jpg

Modified:

post-17573-0-28996700-1497041610_thumb.jpg

Smoke limiter next - this requires a bit of maths.

Diesels produce max power with no/minimal visible smoke at around 18-20:1 AFR. 

The smoke limiter map compares engine speed against airflow as measured by the MAF. Note that PD cars have several for different engine temps - VE pump cars only have 1 (I think).

You can edit them all, but leaving all except the 80degree one stock will mean the car can't be fully thrashed until it's warm - not a bad thing in my book.

post-17573-0-72733600-1497042323_thumb.jpg

The top column is 1050mg of air, which at 18:1 AFR will only allow us to burn about 58mg of fuel (still much higher than the map currently allows, but not our target 60mg).

Our increased turbo boost will bring us more air, so what we will do is change the axis to take this into account, by right clicking on the axis values.

post-17573-0-82201600-1497042320_thumb.jpg

I changed the last 3 columns, so instead of 850, 900, 1000, 1050 it goes 850, 950, 1050, 1150. 1150mg of air gives us an AFR of 19.1:1 at 60mg of fuel so there should be no smoke.

Once the axis has been edited I used multiply by 1.05 on the 3 rightmost columns until the highest value in the 1150 column was 60mg. 

You can change it so all the values in that column are 60, but I personally like to keep the shape similar to stock.

post-17573-0-54867700-1497042322_thumb.jpg

That's more or less it - how can we tell how we've done?

Handily the software has a function for this.

At the top go to actions>view performance. As diesel has a fixed energy value, the program can predict power and torque based on a few assumptions.

Stock:

post-17573-0-27374800-1497043305_thumb.jpg

Mod:

post-17573-0-54817300-1497043318_thumb.jpg

Great success!

Now you may note that I haven't always given any exact values to use here, I don't really want this to be a straight "copy me" type affair, anyone doing this for themselves should understand what they're doing and why. 

Trying a lower level of fuelling or boost first to see what it feels like would be a good idea.

Do plenty of messing before flashing to your car and feel free to post up for advice.

Please also remember that all this is at your own risk, tuning is fairly safe but if you change the wrong numbers you can break stuff big time.

Have fun.

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I shall also chime in on occasion to say one of 2 things:

 

1. Dave_q knows his onions re the mapping malarky

2. MOAR BOOST.

 

seriously though, as Dave says in the first post, any such changes are at your own risk. I've mapped 4 cars so far using the teachings and knowledge this thread will contain and had no problems.

 

That said they were also cheap chod that was essentially disposable to me.

 

Dave, I think we may also want to list commonly available cars/engines that can be mapped? Does the forum have a "List" function?

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On 05/06/2017 at 22:01, 320touring said:

I shall also chime in on occasion to say one of 2 things:

 

1. Dave_q knows his onions re the mapping malarky

2. MOAR BOOST.

 

seriously though, as Dave says in the first post, any such changes are at your own risk. I've mapped 4 cars so far using the teachings and knowledge this thread will contain and had no problems.

 

That said they were also cheap chod that was essentially disposable to me.

 

Dave, I think we may also want to list commonly available cars/engines that can be mapped? Does the forum have a "List" function?

Cheers chief. 

Yeah I will put up a list of what we know to work in the reading/writing post when I get a chance - this will possibly be Thursday or Friday night.

That said, I really just want to concentrate on VAG stuff here as it's the easiest DIY by far - as you're discovering with the Alfa it's a lot more work to find and change the maps for most other stuff.

As a side note, all this information is available elsewhere on the internet, but the tuning forums give a bit of a closed shop vibe - they're often a bit funny with total noobs trying to learn unless they think you've already put some work in.

Perhaps this is because many of them make a good living charging £200 or whatever to map other people's cars, who knows.

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Top work, and having expereinced Neils Octavia with a remap I can vouch for the results!

 

Have you ever played with Bosch Motronic? The Locost runs 2.8 which is apparently good at adapting to mods, however it would be nice to get the rev limit a wee bit higher! Am I right in saying it's an old fashioned solder in a new chip type job? 

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On 06/06/2017 at 08:50, dome said:

Top work, and having expereinced Neils Octavia with a remap I can vouch for the results!

 

Have you ever played with Bosch Motronic? The Locost runs 2.8 which is apparently good at adapting to mods, however it would be nice to get the rev limit a wee bit higher! Am I right in saying it's an old fashioned solder in a new chip type job?

I've only messed with diesels as it's much easier to blow up a pez engine with a bad tune.

However a quick Google says that, yes it's a chip job, but the ECU may already be socketed as standard, crack it open and have a look.

If so you will need a Willem programmer or something to read the chip and write to a new one.

I'd be happy to help with the rev limiter but would recommend any actual tuning on a pez engine is done on a dyno by a pro.

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I'm going to watch this very closely. I've looked into the remapping side of things briefly on the 90 hdi. I don't want to lose reliability by doing something very silly but a little bit more power would be helpful and maybe a bit more mid range torque. Is this doable by a remap as most sites I've looked on seem to be just about how much power it can push which I believe will have a detrimental effect on reliability. Thanks guys.

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Well the beauty of doing it yourself is that you get to decide how far to go. 

Many remaps, including professional efforts, just have all the maps turned up by x% which is not good tuning.

Understanding a bit of the theory and doing it yourself means you can take it a bit at a time to find a level you are happy with. 

I'm afraid it's not as easy for HDis though - some can be read easily over OBD (Bosch management) some can't (Siemens) and either way it's more work to find and edit the maps.

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Yes, basically that^.

Of course we are all responsible, law abiding adults and inform our insurance of these things.

320t only paid a very small amount extra for the remapped Octavia, 30 quid or so seems to ring a bell.

But yes, the only way to tell it's been done is either to read the map and compare it to stock, or possibly some dealer lever diagnostics may be able to report the car has had a software update - neither of which seem to be standard practice if you've wrapped your car round a bus full of nuns.

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So let me get this straight, you want to make something that is so lethally poisonous, that even the manufacturer only gets it to pass legal standards, which aren't very favouravble to public health to begin with, by cheating on a scale clearly proving the fact it's run by clinical sociopaths, more lethally poisonous for fuck all reason?

 

It's time they pull the plug on diesel cars once and for all.

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Interesting stuff team, will look into it when I stick the spare AFN engine in something.

 

Would this also work with my 1.8T?  Obv I know they can be remapped, but not sure on the process. I was thinking of experimenting when I've ironed out the niggles.

In theory it's still boost map, air/fuel ratio, torque limiter, injector duration etc?

 

Badger5 ( to have a lot, but wondered if you chaps have any experienece

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So let me get this straight, you want to make something that is so lethally poisonous, that even the manufacturer only gets it to pass legal standards, which aren't very favouravble to public health to begin with, by cheating on a scale clearly proving the fact it's run by clinical sociopaths, more lethally poisonous for fuck all reason?

 

It's time they pull the plug on diesel cars once and for all.

 

Because GLF

 

Go Like Fuck

 

Go Like Fuck

 

Go Like Fuck

 

HTH

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RE: the 1.8T - yes I think you can read/write using the methods described above depending on year/engine code, but you would need to find a way to find and edit the maps - the software I use only does Bosch EDC (electronic diesel control) whereas the 1.8T runs Bosch Motronic.

The basic principles are the same but I cannot repeat enough to exercise caution - with a diesel you are always running lean (18:1 - 22+:1) so running a bit less or more lean is fine - with a petrol if you run too much leaner than stoichometric you will get too high exhaust gas / in cylinder temperatures and melt something eg pistons or turbo.

Nefmoto (nefarious motorsports forum) is meant to be a good place for 1.8T tuning.

LP: Dunno really, can you find your ECU and pop up a picture or a part number to check it is readable?

If it is meant to be readable I would do a check with VAGCOM or something to confirm that you can connect to the ECU and there isn't a wiring problem to the OBD port.

If all that checks out and MPPS still won't read, you could try Galletto instead - sadly the warranty provided with the ebay pirate wires is poor at best - I did once have a Fabia that wouldn't read, despite the same wire reading a near identical Fabia the same day.

Junkman: Valid points, I will respond later when not at work.

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So let me get this straight, you want to make something that is so lethally poisonous, that even the manufacturer only gets it to pass legal standards, which aren't very favouravble to public health to begin with, by cheating on a scale clearly proving the fact it's run by clinical sociopaths, more lethally poisonous for fuck all reason?

 

It's time they pull the plug on diesel cars once and for all.

Isn't it roughly in line with the GGG 'warm up the planet' plan? Just with moar clag

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On 08/06/2017 at 10:53, Junkman said:

So let me get this straight, you want to make something that is so lethally poisonous, that even the manufacturer only gets it to pass legal standards, which aren't very favouravble to public health to begin with, by cheating on a scale clearly proving the fact it's run by clinical sociopaths, more lethally poisonous for fuck all reason?

 

It's time they pull the plug on diesel cars once and for all.

 

I'm going to break this answer up a bit. 

Are diesel cars poisonous?

Well yeah, of course they are. I cannot deny this. All forms of exhaust gas are bad if you hang around them too much - we breathe the oxygen, not the carbon dioxide.

But diesels are way worse than petrols, yah?

Hmmm. Not sure on this as it's hard to make an apples for apples comparison. The age of car we are likely to be looking at is probably similarly clean to a similar age petrol, maybe a bit more NOx and particulates but less CO and unburned hydrocarbons. 

I understand that NOx and particulates are the current baddies du jour, and it's hard to deny that for a modern car the diesel is worse on this front. Hilariously (or not if you live in a city like London) the increasing emissions regs may have actually made this worse. 

Basically the conditions that promote thorough combustion and burning off soot (PM) are the exact opposite of those required for low NOx. The NOx is created due to a phenomenon called dissociation, where because of extreme temperature and pressure in the combustion chamber, the N2 and O2 molecules in the air debond and bond to each other. In these conditions though, the majority of soot will be burnt off.

To reduce NOx you can reduce in-cylinder temperatures to reduce dissociation of air. But this means you get more PM.

post-17573-0-04907000-1496953076_thumb.png

So what do manufacturers do? Many of them pick one end of the graph and deliberately generate more of one and less of the other to get away with only using 1 type of aftertreatment - generate more soot and have a DPF, or generate more NOx and have either an SCR/adblue type system or an aggressive EGR rate.

Sadly, as well documented, this has been implemented either badly, or in a manner designed to circumvent the rules. This is combined with trends for ever increasing injection pressures and combustion temperatures mean that the modern dizzler is probably chucking out more NOx than our old clunkers.

http://www.fleetnews.co.uk/news/fleet-industry-news/2017/01/09/nox-emissions-from-euro-6-diesel-cars-more-than-double-modern-diesel-trucks-according-to-new-study

Although if we're talking modernz, petrol cars aren't saints and can chuck out a fair amount of NOx and PM as well - again due to increasing injection pressures and direct injection.

So will remapping my car make it chuck out more nasty shizz?

In a word, no, if done properly.

When I get round to writing up my how to it will include details on using the smoke limiter map to make sure you are running at an acceptable AFR. For the tree huggers I will not publicly post any details on circumventing emissions control systems such as EGR.

A badly done remap will almost certainly end up with more harmful emissions. One done with some understanding of maths and engines will be simply changing the cars calibration to something more like another model in the range - most of the engines we are talking about were available from the factory with a higher rating. 

Of course, I cannot deny that there will be some increase in exhaust emissions when the additional power is used, but unless you drive flat out everywhere it will be negligible over the life of the car.

Whether this is better or worse for The Environment than driving round in a Yank V8 with a 4 barrel carb is a matter for the individual to decide. :) 

I personally think people should be able to manage their own cars and lives without excess gubbermint intervention, so would never propose banning diesels in the way Junkman seems to be suggesting.

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This is all good stuff, I did my own map pissing about on my 1.8t Ibiza Cupra. 

When you don't have a VAG diesel, you generally don't have the luxury of having a bit of software with all the map tables laid out for you. There's some definitions for common VAG stuff, but outside that you'll spend hours just looking for the map you need to change and working out the scale.

Then you change it and realise there's another one limiting it, which you need to find, and change too.

 

I managed to turn up the boost and sort out the timing on my Ibiza, but the map for "target AFR" had another map that delayed the target AFR by 2 seconds, which I couldn't find - I needed to turn the fuel right up at peak boost, but it was always lagging and I was scared I'd blow it up.

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