GR Yaris Finetuning the original for driving fun and reliability

Yeah, like most modern turbo cars, it runs hot. I prefer a 'cool' car 😅, it's more fun to drive.

Speaking of, what peak EGT's (Cat Temp Bank 1?) are people seeing with different set-ups?
 
My cool air to flap hack isn't going so well. Tried a few different hose options, either hoses are too big to pass the shifter mechanism without pinching them in too tight bends, or the hoses are too small to bring meaningfull amounts of cold air to the flap.
@DeanoC your little 3D elbow, how effective is it for IAT's logs?

The Helmut 3D printed intake is fairly effective vs OEM, 10+ logs per set-up show roughly halving IAT rise in 3rd gear pulls to redline from 15-20°C to 7-10°C, depending how hot the engine is. However not sure if that gain holds up on constant flap open driving, average difference is then maybe 5 degrees. All good however it's... well not very pretty.

Usually I'm not a sucker for ££ bling but I really like the engineering+CF look of the Forge inlet duct... Maybe I should just indulge...
 
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I'd say bugger all difference. It's all on the cooler side. Just easing off the throttle for 5 seconds at 100mph + before braking a bit later on a straight will make more IAT improvements from charger soak than any pipes or scoops will on the inlet side.
 
DeanoC said:
I'd say bugger all difference. It's all on the cooler side. Just easing off the throttle for 5 seconds at 100mph + before braking a bit later on a straight will make more IAT improvements from charger soak than any pipes or scoops will on the inlet side.
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I'm thinking a little elbow won't do much, there still is a flow through the engine bay that will make it miss its mark.
Backroad driving on very small roads is different again too, so I'm set on reducing the >+20°C above ambient charger temps as much as possible. From my findings so far I've now set my mind on the Forge.
 
Onehp said:
I'm thinking a little elbow won't do much, there still is a flow through the engine bay that will make it miss its mark.
Backroad driving on very small roads is different again too, so I'm set on reducing the >+20°C above ambient charger temps as much as possible. From my findings so far I've now set my mind on the Forge.
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Go for it
 
Onehp said:
I'm thinking a little elbow won't do much, there still is a flow through the engine bay that will make it miss its mark.
Backroad driving on very small roads is different again too, so I'm set on reducing the >+20°C above ambient charger temps as much as possible. From my findings so far I've now set my mind on the Forge.
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Mine is never that much higher on the road unless I'm in traffic. It seems to sit about 4-6 agrees above ambient max.

That air I take is for general engine bay cooling including the box.
 
DeanoC said:
Mine is never that much higher on the road unless I'm in traffic. It seems to sit about 4-6 agrees above ambient max.
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Same for normal driving. I enjoy driving very small very twisty roads. Meaning short bursts of full throttle, closed throttle (no IC flow) and relatively low speeds...
 
Onehp said:
Same for normal driving. I enjoy driving very small very twisty roads. Meaning short bursts of full throttle, closed throttle (no IC flow) and relatively low speeds...
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Got you, sounds very similar to me. Outside of the run in period I've never used mine for normal driving unless it's driving to a track or to get work done at a garage.

Maybe my de-gpf helps general engine bay temps, cat 1 temps are easily 200-300 less than before on average I'd say.

I'll be interested to see what you discover. Heat is certainly no.1 enemy of this car.
 
DeanoC said:
Maybe my de-gpf helps general engine bay temps, cat 1 temps are easily 200-300 less than before on average I'd say.

I'll be interested to see what you discover. Heat is certainly no.1 enemy of this car.
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That's massive. HJS should have a similar effect, albeit maybe not exactly as big a drop. Stock cat1 temps are so high, I'm amazed a box only would render any meaningful power and if it does it's because it is running hotter then it should for anything else then single pulls....

Me too, after my little plan is done I hope it runs a lot cooler = more fun and healthier.
 
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Onehp said:
That's massive. HJS should have a similar effect, albeit bit not as big a drop. Stock cat1 temps are so high, I'm amazed a box only would render any meaningful power and if it does it's because it is running hotter then it should for anything else then single pulls....

Me too, after my little plan is done I hope it runs a lot cooler = more fun and healthier.
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You're right. When I was configuring my tuning box EGT was my main concern., Looking at the numbers thinking this can't be right! We could really wind it up when the GPF went. It also cools off a lot quicker.
 
@Michael Knight share an interesting video here: https://www.gr-zoo.com/threads/intercooler-performance-and-lag.611/post-8296

I thought I would comment it more here beyond the IC. It is very interesting as it is showing live logging data. Some things I noticed:
- Dyno limitations: ambient was 24 degrees, IAT started at an high 48 degrees C (heat soaked) and at times raised above 60 degrees. Charge temps were lower but still hit 50 degrees, so at the very limit and therefore very interesting.
- Even so, stock IC allowes it to make the power it wants as timing is up, and boost is as commanded.
- This car has OPF delete, so completely stock is worse
- The added box didn't add power, increased EGT and interestingly, the ECU doesn't pull timing but actually pulled boost (or what it thinks is pulling boost) so we can see the box wants to add anything between 0,2-0,3bar but the ECU says no, too hot folks.
- This shows us that adding a box on a fully stock car and even a remotely hot day, won't do much to help....

And related to this refining, the stock IC is actually quite well dimensioned for stock power, my goal with the IC and low IAT isn't power, but NA and boost (low lag) response. However, added benefit, it will both give some top end power and give heat headroom to add some boost right before the redline (together with HJS that has similar effect as an OPF delete) for that lovely sense of revving out an engine...
 
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Have been pondering the software tuning options now that remaps are available. My conclusion is that if one has a great local tuner that one trusts and just wants to set something and be happy with it, a remap is an option. However, here the focus is on finetuning the original, implying iterations to find the optimal in one's own driving and own control of how power delivery influences driver experience. Moreover, main improvement comes from improving the hardware and respecting the limits of said hardware by logging and keeping temps down, so not to experience soak/lag and at worst, power cuts as conditions become less favorable which imho ruins the driver experience.

Self-programmable ecu even better but too much money (Syvecs) and wanting to balance everything with longevity, too much torque/power works against that anyhow so really returns are quickly deminishing...

So basically sticking with the original plan and aiming for a programmable box.

PS: IC and Forge intake duct here but not installed (still winter...), HJS incoming, box soon to be decided
 
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Onehp said:
So basically sticking with the original plan and aiming for a programmable box.
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I've never used a 'programmable box'. I'm sure you'll have researched them so should be able to answer this question.

If the box connects in between the engine and the ECU, let assume something goes wrong with the car and the car decides to go into a limp / safe mode to limit further damage until car can be seen by a service centre. How does the programmable box deal with that?

Some years ago I read an article (admittedly it was an opinion, so not scientific fact) that stated that mobile mappers and piggy back tunes in some cases just ramped up boost and advanced timing, but didn't factor in variations in fuel quality, and some of the really cheap 'remaps' actually blocked some of the engines security sensors from triggering or bypassed safety protocol. I have spoken to a few tuners about it as I'd only ever go with recognised tuning houses rather than 'Map on my drive.com' type s**t, but I'd always wondered with a piggy back box what the limitations are, and what potential risks if any it carries.

I see Litchfield offer a 'piggyback' box of sorts alongside a remap option with 24 month warranty, so maybe the boxes are more advanced now, but I know so little about them i wondered if you could shed some light on their benefits over a standard remap layered onto the factory ECU (beyond detectability / resale). TIA
 
@warren_RS3 the box in question is linked in the next post. It's nothing magical, rather it's the approach here that is different.

Main improvement is done by better hardware, that by physics give better driveability and response and that unload the turbo from work, due to better flow and better thermodynamics.

Then, by upping boost again, very little for the most part up to 5-5,5k rpm, we take back some of the margins we added but still on or even below OE levels of (heat) load, and only push a little at the top end for driving enjoyment, not unlike what was done for the GRC. This push is done not blindly, but with automatic logging so that one can always look back how it affects boost (does the ECU allow us to add what we request), and keeping eyes on several other health parameters hopefully, like timing pull, EGT, AFR etc. This part remains to be seen as to our knowledge, me and a friend are the first to publicly (on a forum) try the jb4 (which is still to arrive).

So rather then use a box to push beyond OE established boost limits when circumstances are beneficial, only to cave in as heat quickly becomes an issue and relying on the ECU to pull back on boost one is trying to add and possibly resulting in fault codes, here we (me and friend and anyone else on a similar path) are first creating more hardware headroom for consistent performance even if circumstances aren't ideal, and use a programmable box with (hopefully) proper and very easy to use logging to add a little fun where possible within OE like limits...

Edit: Something similar to the box can of course be done with a remap, but in my case I prefer the box as it gives a lot more control and finetune adjustability in my own driving without the need to frequent a (patient) remapper and physically reflashing the ECU by directly connecting to it (and wait till its done), the whole iterative process is just so much slower, and a proper motorsport Syvecs ECU that one can remap oneself on the fly is a bit much cost wise and just OTT for my modest goals.
 
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Now after driving few miles with HJS and Wagner IC competiotion combo have noticed that less boost is better - engine pulls much smoother, and especially how engine reacts from 0-1bar boost, pickup is smooth and linear. More effortless driving which feels nice.

Sometimes less boost is more.
 
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