I see that a variety of very shiny catch cans are sold for the S2000. I'm familiar with their requirement on track cars, and I'm familiar with the return hoses that usually run to the valve covers on street legal smogged cars. My question is, if I install a catch can on a street vehicle, will the smog computer notice if there's no more vaccum on the line, or does one run a line from the catchcan output vent to the engine input? If the latter, does the can actually do anything useful, or does it just look spiffy?

 

Catch can line runs from the crank case to the catch can back to the intake. On a street car, they are not really necessary. Some will argue that they are not necessary on ANY car, but turbo cars or high performance cars are subjected to much more harsh conditions and may benefit from making sure that any oil/oil spray stays OFF underhood components and out of the intake.

That being said, I plan on adding a cheap/smaller one down the road in the area where my air pump is. Probably won't be able to see it, and that's how I want it.

 

very necessary for any s2000, there's a good size of oil to be "caught" in most of the s2000 i worked on.

 

^ ... not so much, on a stock S2000 there is no reason to have one. You want one for forced induction, especially high boost because you are no longer "sucking" the positive crank case gases out as you would when you are naturally aspirated. Rather your forcing air in and not letting the engine breathe.

 

I heard that a catchcan can help with the oil cossumption on earlier AP1 models. Is this true?

 

there is a difference. even on NA s2000, when u hit vtec, smoke will come out of the exhaust. after putting the catch can on, there isnt smoke that comes out. the PCV can only hold so much pressure

 

MY03 has a DIY catch can and all i really do is DD it and it has caught alot of oil in there. so i see it benefiting anyone.

 

I have a GReddy can that I put on.. oil consumption has dropped considerably

 

A catch can will help most cars. It's either catch it or burn it.

 

do you have one yourself?

i'll show you a picture of my catch can when i am doing my oil change, i got more oil in there stock than i have running a t3t04 on my accord