[GR86Talk]

What I find interesting is that the GR86 Japanese Domestic Model gets 232 HP at the flywheel vs GR86 United States domestic model gets 228 HP at the flywheel per Toyota published specs. The Japanese version has 4 more HP. One difference… the Japanese Domestic doesn’t have that carbon screen while the USA one has the carbon screen. Hmmm…

 

[Wayward67]

They also don't have Cali gas. Not sure if the 86 is measured at the worst fuel, best or random.

 

[GR86Talk]

I think US spec states premium 93. Since they list it specifically, I would assume that is what everything is based on, at least for US. Is Cali gas bad?

 

[EmperorJJ1]

I think US spec states premium 93. Since they list it specifically, I would assume that is what everything is based on, at least for US. Is Cali gas bad?

its just a different requirements for refining thus a different formula. i dont know much about it other than that.

 

[TRU-BOOST]

The manual does state 93 octane specifically and that even 91 will reduce power.

 

[Ritter]

What I find interesting is that the GR86 Japanese Domestic Model gets 232 HP at the flywheel vs GR86 United States domestic model gets 228 HP at the flywheel per Toyota published specs. The Japanese version has 4 more HP. One difference… the Japanese Domestic doesn’t have that carbon screen while the USA one has the carbon screen. Hmmm…

Could we assume or infer that the JDM vehicle does not have the US 50-state tune either?

 

[GR86Talk]

Could we assume or infer that the JDM vehicle does not have the US 50-state tune either?

There is a US 50-state tuned cpu vs JDM?

 

[Boomer2677]

What I find interesting is that the GR86 Japanese Domestic Model gets 232 HP at the flywheel vs GR86 United States domestic model gets 228 HP at the flywheel per Toyota published specs. The Japanese version has 4 more HP. One difference… the Japanese Domestic doesn’t have that carbon screen while the USA one has the carbon screen. Hmmm…

I just want to make sure, but you’re referring to the screen that’s under the air filter in the air box, correct?

 

[Ritter]

There is a US 50-state tuned cpu vs JDM?

I don't know if there's a JDM tune or not. There is certainly a US 50-state tune and it seems reasonable to think that there could be a JDM tune because JDM vehicles don't need to pass US certification.

 

[GR86Talk]

I just want to make sure, but you’re referring to the screen that’s under the air filter in the air box, correct?

Yes

 

[Boomer2677]

Yes

👍

Thanks. You always seem to know what you’re talking about, and certainly know a lot more than me. So I am going to take what you say about the carbon screen being absent in units sold in Japan as something I can get rid of without worrying it may cause a problem. Seems to be a much better and cheaper way to gain 5 or 6 Hp than an intake.

I am still curious why this carbon screen is in the U.S.-sold units? I would guess it has something to do with some mythical government environmental concerns.

 

[EmperorJJ1]

👍

Thanks. You always seem to know what you’re talking about, and certainly know a lot more than me. So I am going to take what you say about the carbon screen being absent in units sold in Japan as something I can get rid of without worrying it may cause a problem. Seems to be a much better and cheaper way to gain 5 or 6 Hp than an intake.

I am still curious why this carbon screen is in the U.S.-sold units? I would guess it has something to do with some mythical government environmental concerns.

correct all new cars must have a carbon filter per US regulations

 

[EmperorJJ1]

 

[Duchess]

Japan, Europe, US are all different standards and the US has two standards. I believe Japan also has higher octane fuel, but it might be a difference in measuring, I don’t remember. Whatever the case, they’ll all have different tunes and probably some different equipment. This might be outdated, but Japan used to have lower standards and US CA the highest, but now Euro and US are somewhat equivalent, but they have different limits for different chemicals, so it kind of depends on what respective chemicals you’re talking about.

 

[Wayward67]

Japan, Europe, US are all different standards and the US has two standards. I believe Japan also has higher octane fuel, but it might be a difference in measuring, I don’t remember. Whatever the case, they’ll all have different tunes and probably some different equipment. This might be outdated, but Japan used to have lower standards and US CA the highest, but now Euro and US are somewhat equivalent, but they have different limits for different chemicals, so it kind of depends on what respective chemicals you’re talking about.

Essentially yes.
We use AKI with is the average knock [index] I think.
It's the average of research octane Number RON and Motor octane Number MON. 98RON should be equal to 93AKI. I think Japan has 100RON available.

Cali 91 is known as pisswater in certain communities as it's even worse than the Number would suggest.

The carbon filters are there for the same reason (one of them) that our gas cans are a joke. Fuel vapors and government officials thinking they understand how things work.

 

[Boomer2677]

Final question:

Are you doing anything illegal by removing this carbon filter? And can Toyota get on your ass and create a warranty issue for removing it?

 

[Duchess]

The government doesn't dictate the manner of equipment, just the standards that need to be met. It is the OEM's engineers who meet (or cheat) those standards. It might be illegal to remove it as it is altering emissions equipment, but I can't imagine anyone would notice if you do. This is not the evaporative emissions canister that captures unburned fuel vapor for later burning to prevent it from venting to atmosphere. If you ever walked past an old car on a hot day and smelled gasoline, that's what that canister captures (along with the sealing fuel cap). I imagine this filter is a secondary, passive capture part for whatever might be in the intake tract after shutdown, which I would think is of minimal use on a largely DI engine, but someone with a degree I don't have thought it needed to be there.

 

[TRU-BOOST]

The charcoal pad is a cheat by the manufacturers. It does not even do what they claim it does. Vapors never move backwards out the air filter. It was a 25 cent "fix" to keep the EPA off their back while they leg hump the EV manufacturers.

 

[GR86Talk]

What I find ridiculous is they plastic weld the carbon filter or charcoal pad or whatever you call it to the upper air box. So that if you need to replace it, you have to buy a whole upper air box. What if you keep your Toyota 250,000 miles… that filter would have to be way more restrictive and honestly after 25,000 miles activated carbon would probably not be very active anymore. That said, It isn‘t too expensive to replace the upper air box, like $70 discounted from Subaru and $80 discounted from toyota. But still sort of ridiculous they made it part of the whole intake. I bought a new upper air box and ripped out the pad and kept my original on the shelf just in case I need it in the future.

 

[chrisz5z]

What I find ridiculous is they plastic weld the carbon filter or charcoal pad or whatever you call it to the upper air box. So that if you need to replace it, you have to buy a whole upper air box. What if you keep your Toyota 250,000 miles… that filter would have to be way more restrictive and honestly after 25,000 miles activated carbon would probably not be very active anymore. That said, It isn‘t too expensive to replace the upper air box, like $70 discounted from Subaru and $80 discounted from toyota. But still sort of ridiculous they made it part of the whole intake. I bought a new upper air box and ripped out the pad and kept my original on the shelf just in case I need it in the future.

Is a bit odd considering Subaru has used a removal charcoal panel in their other vehicles. Wouldn't be surprised if it was Toyota's decision to save a few pennies.