Yes, I know about the pressures written inside the door, but should they be done on cold or hot tires? Anyway, I went to two tire dealers and they both told me: "leave them like this" and I trusted them, but sometimes they seem too high pressure.
GR Yaris (Gen 2) GR Yaris Mk2 (MY2024->)
- Thread starter Michael Knight
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spectre7
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I assume cold so you wont trigger the warnings. To clarify its not like car becomes undrivable when tires are at 2.5 when cold, for normal driving within the speed limits etc. it is ok. But once you start pushing the car through the corners those 2.5 can easily climb to 2.7s, even 2.8s on hotter days. At those pressures you can definitely feel less grip and more understeer on Michelin Sport 4s, at least in my experience. Few weeks ago we had a solid heatwave and I had to park my car on the sun, they had ~2.7 pressure cold but I was in a hurry so I had no time to deal with it. In corners less grip and resulting understeer was definitely noticeable, even though I was driving less dynamically than usual knowing the situation.
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They measured them for me when they were "hot" but I was driving slowly... However, in my opinion, since all 4 were the same, they were still wrong in my opinion... As soon as I can, I'll fix them cold in the garage so I can also try with the right pressures, because these tires always seem a bit slippery to me, the display shows 2.4-2.5 on all 4
its better to have it highish vs lowish. I usually run around 2.2-2.5bar.
spectre7
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2.2 is optimal for our current weather here in Slovakia, I run 2.2s in front and 2.1s in rear tires.
does it matter? pressure is the pressure what it is.
I'd adjust per tyre spec/model what works best for the tire in the conditions. there is differences between tires.
New Whifbitz exhaust fitted this week and EcuTek tune adjusted made 323bhp, slightly disappointed was expecting a bit higher but there’s still a torque limit that’s holding a few horses back so hopefully that will be cracked soon enough (I did try a map the other week but it didn’t solve it).
What supporting mods do you have? Seems that Whifbitz tunes and dyno runs often reveal conservative figures. Or maybe some of the others are more generous with their corrected figures perhaps. Or some cars perhaps just produce more horses than others. Still a good figure though and hopefully you’ll notice that in everyday driving.
Eventuri intake
Whifbitz cat back exhaust
Airtec inlet manifold
Airtec turbo elbow
Airtec rear turbo pipe
Airtec intercooler
Flexfuel (not dyno’d on ethanol)
I guess the real big gains come from a sports cat and GPF delete then in terms of hardware. Hopefully you’re happy at least with what should be a noticeable and healthy output over stock and a car that feels more eager even when pootling around town.
It changes, 2.2 when cold will be 2.5 or more when the tire is hot... as we all know, the air expands when it heats up... that's why I'm asking... but I imagine Toyota means cold anyway this weekend I'll adjust it well because I want to see if it improves or if nothing changes
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Here in Italy a well-known tuner has obtained around 350hp and 490nm of torque… with 100 petrol
Maybe they left the torque limiters low for the gearbox? To avoid stress?
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Sans GPF, I did look if HJS did a sportscat for the new model but couldn’t see but think I’ll move on to handling now.
He flashes up a picture of the Yaris Syvecs ECU?
I can only watch pics due to language difference. (Just managed to get auto subtitles working don’t think they work unless in the YouTube app) But there’s a built in torque limit that EcuTek have yet to bypass that limits it to 400nm my understanding is it will momentarily hit 450nm but then bring it back to 400nm.
But the bhp reflects the sports cat so probably about right.
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He has a free downpipe though... I haven't heard of an Ecutek torque limiter that's not yet adjustable. Do you have any more info? I heard the tuner was very satisfied. 350hp and 486Nm of torque are a good result in my opinion... I'm worried about the lifespan of the gearbox, though.
It’s not an EcuTek limiter it’s a Toyota limiter that hasn’t been cracked yet. My car was the test car for EcuTek that had it for a few weeks on their dyno to develop the software. I was then sent a month ago a new tune to do some pulls to test if the torque restriction had been cracked but it was unsuccessful.
However that video is using a hub dyno and not rollers so I suspect the numbers aren’t as different as they read.
I honestly don't know... but someone else on a roller dyno got similar results... if I find the video I'll share it... but it seems strange to me that that dyno gives different results than the roller ones... usually they are similar... what pressures do you run with the turbo? 2.1 peak?
You have a stock downpipe, correct? Those 20 hp losses could be caused by that… the stock downpipe severely limits the ability to increase power.
