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Why don’t turboed Hondas pass emissions?

2687 Views 23 Replies 15 Participants Last post by  EggFoolYung
First of all let me say that I don’t even have emissions testing. So, I am not worrying about which kit to buy or anything. I am just curious, and looking for information.

I know that many, many factory turbocharged cars, even when upgraded well beyond factory specs still remain emissions legal. So why is it so hard for Hondas? Even with relatively low amounts of boost.
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kbrunjes said:
First of all let me say that I don’t even have emissions testing. So, I am not worrying about which kit to buy or anything. I am just curious, and looking for information.

I know that many, many factory turbocharged cars, even when upgraded well beyond factory specs still remain emissions legal. So why is it so hard for Hondas? Even with relatively low amounts of boost.
They wouldn't pass the visual inspection, because there is a non-factory turbo in there. That's all. As far as smog goes, it'll pass those as long as it's tuned (ie, not running too rich) and there is a catalytic converter somewhere on the exhaust path still.
I think a lot of it has to do with the wastegate.in some cases the wastegate routes the exhaust (the part that the wastegate releases) so that it cools down to much before passing through the cat or the visual inspection kills some peoples chances.Either that or the poor tuning done to the car (running to rich or lean) or the lack of a cat or properly functioning cat.
its illegal to have your intake system release air into the atmosphere because it might be polluting it. thats why a street legal greddy turbo kit becomes illegal with a blow-off valve.
Do the popular Honda turbo kit's wastegates vent to atmosphere, or back to the exhaust somehow? All of the pics that I have seen show the exhaust piping into the wastegate, but nothing out.
You should be able to pass inspection the same way JDM engine swap guys pass, by the tech not realizing what he's looking at. But the real reason turbo cars of any brand have problems with emissions is that the turbo acts as a heat-sink, not allowing the cat to heat up as quickly as a NA car. Most turbo cars pass everything BUT the cold-strt emissions as long as they are not running too rich. That's the reason that there are almost no non-diesel turbo cars in the US. the only ones I can think of are the VW/AUDI 1.8Ts, Saabs, Volvos, and the WRX. VW solved the problem by using a small-ass turbo, and the WRX has three cats including one BEFORE the turbo.
i'm glad i dont have to worry about all that emissions stuff. I will have to one day though.most likely.
94HBsi said:
its illegal to have your intake system release air into the atmosphere because it might be polluting it. thats why a street legal greddy turbo kit becomes illegal with a blow-off valve.
What are you talking about? That's not illegal and the Greddy kit comes with a BOV. It may be illegal to have the wastegate route to the atmosphere instead of to the exhaust path (if that's what you're talking about) but the greddy kit uses an internal wastegate.

I agree with most of the responses here. And Hondas do pass emissions with turbo kits. You need to be properly tuned (not leaking fuel out the tailpipe).

Don't forget the Eclipse GST/GSX, Galant VR4, Supra, RX-7, 3000GT, and 300Z. The reason that the WRX has 3 cats is to that it could be certified ULEV. Subaru could have easily produced the WRX with high HP with one CAT but they wouldn't have gotten it certified as an LEV vehicle....let alone a ULEV vehicle. I mean come on, my 2000 Si (in stock form) puts out more pollutants than a WRX.
I was talking about new cars. Hell, I own two factory turbo cars but they sure aren't 2002's:D
So basically, If I turbo my F22 I'm *ucked?
if you read the past threads about this subject you will see that having a blow-off valve or intercooler kit for a greddy turbo kit automatically voids the legality of it.

illegal parts on car = no pass visual inspection
94HBsi said:

illegal parts on car = no pass visual inspection
There, that sums it all up.
Some people have trouble passing emissions, but yet you drive down the highway and see Tractor-trailer spewing out black smoke into the air... One shift puts out more than my turbo'd b18C does in a year... What gives ?!?!
Dr Drew said:
Some people have trouble passing emissions, but yet you drive down the highway and see Tractor-trailer spewing out black smoke into the air... One shift puts out more than my turbo'd b18C does in a year... What gives ?!?!
haha serious i see those everywhere in So Cal, makes you wonder what the hell is going on.

But yeah i was also wondering what made hondas not pass smog test with turbos. The guy i go to for my smog test said to run my car on the freeway alittle while before coming in, i think that should warm up your cat enough for the cold start test.
Diesels burn clean, despite all the smoke you see those tractor trailers blowing.
94HBsi said:
if you read the past threads about this subject you will see that having a blow-off valve or intercooler kit for a greddy turbo kit automatically voids the legality of it.

illegal parts on car = no pass visual inspection
How does an intercooler void the leagality of a turbo system?
its not CARB approved. look at the civic apexi turbo kit, if you get the intercooler or fuel system it automatically voids the CARB number. also, it works like this... lets say you have a CARB legal greddy exhaust... and a CARB legal greddy turbo kit. although they are both legal, you are no longer legal or some shit. dont ask me... there was a decent size thread about this a few weeks ago. someone back me up here? :confused:
They don't have emissions here in Upstate New York but they have this safety inspection. Anyone know what this safety inspection entails?
Diesels can pass emissions with all that black smoke, because that smoke is known as particulate matter, or soot, and it's completely different than hydrocarbon emissions. Soot is usually plain carbon (like the graphite in your pencil), whereas un-burned hydrocarbons lead to all kinds of nasty stuff, like acid rain, and holes in the ozone layer, and little kittens being killed, etc.....

Emissions requirements have always been ahead of technology. Since the Clean Air Act, fuel mileage regulations have been relaxed about once every two years, as the general public is simply not interested in purchasing vehicles that get 40 mpg. Too many Expedition-driving soccer moms.

In fact, the Expedition/Navigator can not be sold in California, because it's cold-start emissions are too high.

Cold start emissions come more from the excessive fuel being dumped into the cylinder to allow combustion to happen moreso than it does from the turbo acting as a heat-sync. The University of Texas at Austin is working on a distillation system that takes the highly-volatile factions out of gasoline to enable lower cold-start enrichment multipliers. This system has proven to reduce cold-start emissions by 70% in the Navigator/Expedition. Cool stuff.

Nick
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Nikolai said:
Diesels can pass emissions with all that black smoke, because that smoke is known as particulate matter, or soot, and it's completely different than hydrocarbon emissions. Soot is usually plain carbon (like the graphite in your pencil), whereas un-burned hydrocarbons lead to all kinds of nasty stuff, like acid rain, and holes in the ozone layer, and little kittens being killed, etc.....

Emissions requirements have always been ahead of technology. Since the Clean Air Act, fuel mileage regulations have been relaxed about once every two years, as the general public is simply not interested in purchasing vehicles that get 40 mpg. Too many Expedition-driving soccer moms.

In fact, the Expedition/Navigator can not be sold in California, because it's cold-start emissions are too high.

Cold start emissions come more from the excessive fuel being dumped into the cylinder to allow combustion to happen moreso than it does from the turbo acting as a heat-sync. The University of Texas at Austin is working on a distillation system that takes the highly-volatile factions out of gasoline to enable lower cold-start enrichment multipliers. This system has proven to reduce cold-start emissions by 70% in the Navigator/Expedition. Cool stuff.

Nick


dude what are you talking about the expedition/navigator cannot be sold in california? Of course they can be sold here. where did you get this info from?
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