7203 Fitted yesterday.

[aboo]

Fitted this yesterday It has fuel cut upped but I haven't turned up the boost yet.

7203 ECU 1.jpg7203 ECU 2.jpg

[elnevio]

About time I had the boost upped with my 7203 too!

[adaxo]

Is any guide/how to available here??

[Subaru ETA]

A guide how to fit it?

1) unplug old ecu
2) plug in new ecu

[elnevio]

3) Press loud pedal - a lot!

[adaxo]

very funny

[foxdie]

I think he means a guide to raising the fuel cut limit

I've thought about writing up a clear-English guide on how to tune VR-4 ECUs including a quick-starter download package, but then I realise that I'm shooting myself in the foot, it's a maHOOsive can of worms if someone blows up their car following my advice, it can only reflect badly on me.

Maybe if there's enough demand and sanity I may do so

[adaxo]

Yes Jason you right, simple guide 'how to rise boost' will be handy for many of us with flashable ECUs

If you worry about side effect, just write simple disclaimer (as Kenneth did) or send me via PM

So far I find this 'guide' but is a bit too simple

You dont need a copy. Just set your fuel values with wideband, they will have to be made a little leaner all the way from load 120
Like so that 9.8 from the original map is somewhere around 10.8. Depends on many things.

Then add some advance to load 120-140. 160 may be the original. 180 has to be -1 or something 200+ -2 or something

Remove Fuel cuts

WGDC to 100% in the two maps

BDEL to 160 in all four maps.

Then you should have your extra 30-40 hp. THIS IS A GENERAL GUIDELINE FOR TUNING A VR4, nothing more

If you Jason (or anybody) could extend this a bit further will be great.

[foxdie]

If you Jason (or anybody) could extend this a bit further will be great.

Sorry Adam, forgive me for being blunt here, that guide you've written there is incredibly dangerous! It's lack of understanding like that which causes people to blow their engines, that's the reason I was thinking of writing a guide.

Again, I'm sorry to say it, but if anyone enacts those steps above, your car will go bang, VERY quickly!

[aboo]

A how to guide would be great Jason. If you made it clear its at your own risk I'm sure that would cover you from any backlash.

[adaxo]

Sorry Adam, forgive me for being blunt here, that guide you've written there is incredibly dangerous! It's lack of understanding like that which causes people to blow their engines, that's the reason I was thinking of writing a guide.

Again, I'm sorry to say it, but if anyone enacts those steps above, your car will go bang, VERY quickly!

Yes, as I said above, that sounds well to simple and I didn't write that, its was found on here looong time ago, come on Jason, have a mercy

[foxdie]

Yes, as I said above, that sounds well to simple and I didn't write that, its was found on here looong time ago, come on Jason, have a mercy

I knew mercy once, I saw a fellow brit shouting it whilst being beaten by a Frenchman, he was baffled why the Frenchman wouldn't stop

[Gly]

that and i doubt the average person wants to spend a couple hundred $USD to just up the boost limit. to buy the cables needed.

if your the type of person to DIY this i think your the type of person capable to actually being able to figure out the basic coding

i dont see much point in guides, when you can get the roms here on the forums, with all the average person could want.

[foxdie]

Okay, I'll address why the statements above are dangerous;

You dont need a copy.

This is bad practice, you should always take a backup of the ROM on the ECU before you change it. As a recommendation, use Dropbox (it's free!) to store all your ROMs in the cloud¹, I do and it's incredibly handy

¹ "In the cloud" is a buzzword which means it's stored online and accessible anywhere

Just set your fuel values with wideband, they will have to be made a little leaner all the way from load 120
Like so that 9.8 from the original map is somewhere around 10.8. Depends on many things.

This statement is too generalised, it is very dependent on "many" things. Each car is different and acts differently, on top of that, fuelling mods dramatically change how a car fuels in different circumstances.

Adjusting fuelling takes a good Wideband kit, a lot of logging / power runs, experience and insight.

Then add some advance to load 120-140. 160 may be the original. 180 has to be -1 or something 200+ -2 or something

Again, this is too generalised, and again, every car is different. The stock timing map is actually pretty damn good and shouldn't need changing unless you're going for serious power gains, even then there won't be much that needs changing.

I strongly recommend those without experience do not alter the timing map.

Remove Fuel cuts

This is dangerous, removing the fuel cut (i.e. setting it excessively high, you can't completely remove it) is removing the ECUs ability to protect the engine in certain situations. Ideally, you want to set this +30 to +40 above your target load.

WGDC to 100% in the two maps

Again, this is dangerous, setting the Wastegate Duty Cycle to 100% stops the ECU from being able to throttle it back if boost is building too high, by having it set to 100% you're removing the ECUs ability to detect and compensate for boost spikes.

Our poor little TD03s may not be capable of a lot of power, but because they're small they spool up damn quick and can build dangerous levels of boost in a short period of time. By setting WGDC to 100%, you could easily spike to in excess of 1.8 bar (26 PSI) which risks serious damage to the engine.

Also, there are 4 maps. Please see the next question for more expansion on this.

BDEL to 160 in all four maps.

Equally as dangerous, but for 2 different reasons;

Firstly, setting Boost Desired Engine Load (aka Target Load) to 160 (or rather 159) across the board requires significant supporting mods, given that there is a percentage that gets added onto this (BDLA aka Boost Desired Load Adder), which by default is 40%, you're actually setting the target load to 200 (or rather 199), which is about 1.25 bar (18 PSI), here is a loosely derived Load vs Boost table (please note, this isn't accurate, it's just a guideline!);

loadvsboost.png

Depending on mods, a target load of 199 could be around 310-320 HP, but by this point most ageing VR-4 fuel pumps will struggle and could fail, causing the engine to dangerously lean out. This is the last thing you want when you're running such high boost.

Secondly, by setting the boost to this level across all 4 maps, as with the wastegate, you are removing the ECUs ability to compensate for problems. I'll expand more on this now;

There are typically 4 tables each (High Octane 1 & 2, plus Low Octane 1 & 2) for every one of the following;

• BDEL (Target Load)
• WGDC (Wastegate Duty)
• Fuelling
• Timing Advance

It's not immediately clear why there are 2 tables for each octane level, some theorise they are for Manual vs Automatic, some theorise it's for AirCon Compressor running vs Aircon Compressor stopped. Regardless, it's commonplace to copy / paste the values into both matching tables (i.e. Copy the first high octane table into the second high octane table, but not from the high to the low octane table).

What you should realise however is the difference between High and Low Octane tables. The car starts off running the High Octane tables and continues to do so as long as there is no detonation (engine knock). As mild knock is detected, the engine automatically starts to dial back timing advance (1 degree for every 3 counts of knock), then as knock gets more severe, it starts to adjust the Octane Rating of the fuel. Octane Rating is a sliding scale (0-100%), not a quick switchover, as knock gets worse / prolongs, that rating goes down, this is how much the ECU has started to move over to the Low Octane tables, it's all gradual to find that "sweet spot". Our ECUs by default are programmed to expertly handle a LOT of issues.

That mini-lecture aside, by setting the Low Octane tables to match the High Octane tables, the ECU cannot compensate for faults.

TL;DR: Don't edit the Low Octane Tables unless you know for certain what you're doing

Then you should have your extra 30-40 hp.

Yes, this could potentially be true, however the golden rule of "make sure your car can support it" is imperative here

THIS IS A GENERAL GUIDELINE FOR TUNING A VR4, nothing more

As discussed, no it is not

[adaxo]

Good explanation here Jason, Thanks, now just need to read this 5 times and may start understanding a bit more.

Carsten, all tools for flashing are there, its just lack of knowledge/confidence hold us to start playing with ECU, or may we need a bigger balls??

[Kenneth]

You don't need wideband initially, you can tune using the knock sensor, a boost gauge and some knowledge of what you want to achieve.

It doesn't take a genius to do some logging, check for knock and then adjust some fuel / ignition cells.

If you don't have a decent intercooler, chances are you will just be reducing timing though, to get rid of the knock which is already there.

I say go for it, make small changes and have fun. Everyone starts somewhere. And hey, if you enjoy yourself you might decide to go get a wideband kit and really maximise your tune.

[adaxo]

700x300x76 IC, after market exhaust, K&N, Amsoil, NGK 7s, Innovate MTX-L, Evoscan, all are in place already, LPG system capable to run (healthy!!) up to 400HP in place. I just geting a bit bored now, power wise, and reading nearly everyday on here that ppl running up to 1.2BAR via ecu mods all day long and enjoy, so I just try to follow