GR Yaris Balance of tuning and durability limits

[GRunt]

I very much prefer a remap of the stock ecu over a piggy back. For the tuners I've worked with, an plug ecu is a bridge to close the gap till the ecu is opened up. The boxes often deliver power uns torque, but it's not really possible to fine tune dips and curve and response.

When my finally comes, I will take it to MPS and let them tune for stock power but smooth delivery and quick response with top torque and power at redline. They did this before with about 300 HP as well.

 

[Onehp]

, but it's not really possible to fine tune dips and curve and response.

When my finally comes, I will take it to MPS and let them tune for stock power but smooth delivery and quick response with top torque and power at redline. They did this before with about 300 HP as well.

I have done exactly that with my programmable JB4 piggyback, lots of iterations and finetuning response and top end power, through logging in a wide range of real world circumstances rather then one day conditions...

 

[p3.auto]

I honestly think I prefer piggybacks to remaps - at least where AutoTuner is concerned. Having first hand experience of the sensors that are ignored when remapping the ECU it frankly scares me that people can be so reckless. With a piggyback you still get knock alarms and other critical info, you're just manipulating your boost, fuel and timing while having those safety nets in place.

It's been a while since I looked at AutoTuner so maybe they've cracked more features since then. back when mine was done it was very limited. I heard Ecutek were releasing software but don't know if that has come about yet, and 7Mod seem to be pretty clued up with the stock ECU. But honestly if I didn't have the Syvecs i'd have a tuning box over an AutoTuner remap.

 

[Max]

EcuTek wrote in Feb 23 that they have their hands on the GRC and GRY ECU. That should also make things a lot easier.

 

[p3.auto]

EcuTek wrote in Feb 23 that they have their hands on the GRC and GRY ECU. That should also make things a lot easier.

Yeah i've been hearing of their involvement since around this time last year, they actually have my OEM ECU. Was expecting their arrival on the scene last Summer but from what i've heard they would be the better option when available

 

[MRA3]

No problem. All you need is a K type thermocouple in the downpipe and there’s dedicated pins in the expansion plug on the bottom of the ECU. Your tuner should be able to enable it and set up safety stuff easily enough. Worth the extra £50

I would have imagined that any respectable tuner would include that as a part of the package given the money involved in fitting a Motec/syvecs vs cost of that K type thermocouple. If that’s not the case, I’d be very surprised/wary of that tuner. So, thanks for the info, mate.

 

[p3.auto]

I would have imagined that any respectable tuner would include that as a part of the package given the money involved in fitting a Motec/syvecs vs cost of that K type thermocouple. If that’s not the case, I’d be very surprised/wary of that tuner. So, thanks for the info, mate.

It’s just not a standard fit for the plug and play units. I don’t know of anyone in the UK who’s currently installing them with the ECU but I’d love to be proven wrong

 

[Gazooracingyaris]

With a piggyback you still get knock alarms and other critical info, you're just manipulating your boost, fuel and timing while having those safety nets in place.

I'm not sure it works like that, doesn't the piggyback tell the ecu its making say, 1.2 bar when its actually making 1.4 so it makes more boost to reach the target boost of 1.4bar (same effect with fuel and timing) so you're always working to an offset to whats actually going on. If thats the case the safety nets wont work at the designed limits (at least in regards to adjusting the boost, fuel and timing to compensate for any issues it sees).

On the flip side, I'm not even sure if the above is relevant if its accurate, I've not heard a single incidence of there being an issue/failure with an engine due to one of these piggyback boxes other than the odd limp mode being triggered.

 

[p3.auto]

I'm not sure it works like that, doesn't the piggyback tell the ecu its making say, 1.2 bar when its actually making 1.4 so it makes more boost to reach the target boost of 1.4bar (same effect with fuel and timing) so you're always working to an offset to whats actually going on. If thats the case the safety nets wont work at the designed limits (at least in regards to adjusting the boost, fuel and timing to compensate for any issues it sees).

On the flip side, I'm not even sure if the above is relevant if its accurate, I've not heard a single incidence of there being an issue/failure with an engine due to one of these piggyback boxes other than the odd limp mode being triggered.

Exactly, tuning boxes can still trip P0234 for overboost faults for instance as the ECU still has the safety nets in place

Same with timing, if any advance is even being added the ECU will pull it again via knock detection.

I’ve seen some remaps where knock detection is disabled among other things to time the shit out of them. People just coding out errors until something goes bang.

 

[Michael Knight]

I'm not sure it works like that, doesn't the piggyback tell the ecu its making say, 1.2 bar when its actually making 1.4 so it makes more boost to reach the target boost of 1.4bar (same effect with fuel and timing) so you're always working to an offset to whats actually going on. If thats the case the safety nets wont work at the designed limits (at least in regards to adjusting the boost, fuel and timing to compensate for any issues it sees).

On the flip side, I'm not even sure if the above is relevant if its accurate, I've not heard a single incidence of there being an issue/failure with an engine due to one of these piggyback boxes other than the odd limp mode being triggered.

Not sure if all piggypacks operate same way. at least with JB4 there is full time logging & safety features, of course it relies on stock ECU sensor data.
Would be a nice statistics to gather all the engine defects (from tuning + driver errors) per car, but the known list is short?

 

[p3.auto]

Not sure if all piggypacks operate same way. at least with JB4 there is full time logging & safety features, of course it relies on stock ECU sensor data.
Would be a nice statistics to gather all the engine defects (from tuning + driver errors) per car, but the known list is short?

It’s short for a reason. People want to sell products and don’t want their reputation damaged. I’m aware of several but don’t know the technical reasons for the failures - of course suppliers blame tuners and tuners blame hardware. And drivers will rarely admit they did something stupid

I’m not in the habit of naming places just because it opens the door to all kinds of accusations, it happened to me last year with a garage that left me with a non running car that I had to send to Fensport to fix. But I’m confident that pretty much every tuning place in the UK claiming to be GR specialists has seen failures - I’ve seen engines being replaced free of charge without prejudice which is basically a way of saying “it’s not our fault honest please don’t say anything bad”. People don’t replace thousands of pounds of engine for free without reason…

 

[Onehp]

This is especially with social media. Under the rug. Or own up and take learning, I trust those much more. Much more sensitive with customers and if you already pushed out (prematurely) e.g. 100+ tunes

 

[micsub]

In summary ? Drive the shit out of it but drive it OEM !

 

[Florens]

In summary ? Drive the shit out of it but drive it OEM !

For now.. Let others that want the power NOW break stuff. The limits will be found and a "standard recipe" for "reliable power" will definitely be a thing. However that's not going to be for those chasing big numbers, instead it will just aim to improve drivability all over the rev range.

 

[p3.auto]

For now.. Let others that want the power NOW break stuff. The limits will be found and a "standard recipe" for "reliable power" will definitely be a thing. However that's not going to be for those chasing big numbers, instead it will just aim to improve drivability all over the rev range.

Oh plenty of my stuff has broken. It’s all part of the game though.

Oil pressure sensors don’t seem to like the harmonics of a 3 cylinder engine so spend a lot of time near redline and they like to die

I’ve had a coil pack shit itself

A boost solenoid died

My gearbox mount tore

The replacement oil sensor is now playing up

I don’t think there’s such a thing as “reliable power”. It’s either stock and Toyota sort it out or you tune it and suck it up. Even a stock engine will fail due to valve float or a spun bearing if you’re unlucky

 

[Florens]

Oh plenty of my stuff has broken. It’s all part of the game though.

Oil pressure sensors don’t seem to like the harmonics of a 3 cylinder engine so spend a lot of time near redline and they like to die

I’ve had a coil pack shit itself

A boost solenoid died

My gearbox mount tore

The replacement oil sensor is now playing up

I don’t think there’s such a thing as “reliable power”. It’s either stock and Toyota sort it out or you tune it and suck it up. Even a stock engine will fail due to valve float or a spun bearing if you’re unlucky

Appreciate your input on what has gone wrong for you! Sure, true reliability isn't achievable but I'm talking about a compromise between a bit more power everywhere and acceptable reliability.

 

[Onehp]

Appreciate your input on what has gone wrong for you! Sure, true reliability isn't achievable but I'm talking about a compromise between a bit more power everywhere and acceptable reliability.

And that depends on how you run it. If the car lives on the Nordschleife you will be quite lucky if it's reliable completely stock. And 600hp can be reliable for e. g. 10 minutes devided into sixty ten second pulls spread over 2 years. As a mattter of speech...

 

[Onehp]

The upgrade when you break philosophy will land you in a 1000hp Yaris eventually

Claimed 740hp on hubs (~870hp crank?), that crank 1000hp isn't as far off as we maybe thought...

 

[Michael Knight]

silly figures. that thing must move quite fast..

 

[DrSetup]

And here I am with just over 400 (engine hp) thinking my car is fast.

Wonder what twice the power would feel like?