I was curious about the idea of using an exhaust manifold from a newer civic and putting it into an older civic such as a '92-'00 civic. I figured that the newer manifold would flow better and have better emissions than the older one where the catalytic converter is after the manifold.

 

Simply stated, it wont fit. The motors are completely different.

 

x2

 

i'm not sure what better emissions in relation to an exhaust manifold even really means. however, i think your assumptions may be a bit misguided. newer parts don't equal better performance in many cases.

i'm curious though, which newer civic were you thinking of specifically?

 

Why not get a header then?

 

better emissions come from a more efficient motor. The hardware also play a role, but it's more or less inside the motor before it comes out.

 

I thought I already explained why I think this exhaust manifold is better than the older one in the civics, it's because it heats up faster, more strict standards and might flow better. Are there any replacement headers that could fit that would accomplish the same goals as the '01+ headers?

 

A manifold is a manifold and a catalytic converter is a catalytic converter.

The engine is what makes the car more efficient, and less harmful to the environment. Emissions standards have increased since 2000.

Why not just buy a header and slap a decent catalytic converter on it? You wont notice anything with a new manifold/cat compared to an new, old manifold/cat.

The new type manifolds are just as restrictive as the old ones. You want higher flow, get a header. You wont get any better.

 

he's "justplayin"

 

What you don't GET is that they have manifolds with integrated catalytic converters, and since the manifold is the closest thing to the engine exhaust, having an integrated manifold will cause it to heat up quicker than otherwise. A manifold that heats up quicker is one that will output less emissions and since it'll be OBD-II catalytic converter, it'll also mean I can tune the car better and still pass emissions testing.

Anyways I was asking whether or not anyone knew for sure whether or not the new manifold/catalytic converter combo was more or less restrictive or not, unfortunately nobody can give me any anecdotal evidence.

 

No one is giving you the answer you are looking for because it doesn't exist. We understand what you are saying but the fact is, it just won't work. If you want the cat to be on the manifold buy a y7 manifold. The cat is integrated.

 

I do get it. What you want is stupid. The cat will heat up, just not as fast. Big deal. They aren't efficient at all. I have a D16y7, and I have an integrated cat/manifold. Its junk and doesn't flow at all. A cat is a cat, regardless of the On Board Diagnostics, whether it be OBD0, OBD1, or OBD2.

As far as tuning better... I don't know how you're going to tune it better.

They probably flow just as bad as each other. Does that answer your question?

 

Regardless of any argument of flow and efficiency, IT WON'T FIT. So why continue to argue? The engines were completely different and the manifold from one series of engines will not bolt to the other.

 

QFT. I said that earlier, but I guess it didn't sink in.

 

Actually there is a difference between the cats. An OBD-I cat only has to be 70% effective while an OBD-II cat has to be 90% effective, and as of recently (mar 09?) cars now have to use OBD-II cats when replacing, even if your car is OBD-I. I know it sounds weird to call a cat OBD-I OBD-II but they really are called that.

 

Well, I doubt you will be buying an old cat.

Just buy a header and put a high flow cat and call it a day.

I'm not sure what you are going to tune a single cam for since you obviously aren't boosting it. Efficiency and flow will be pretty good with this setup.

 

Work on advancing the timing, maybe increase compression ratio, working towards better fuel economy, more torque, more efficient, etc. I just don't want the california popos getting their panties in a bunch because my car pollutes more than it should due to my "efficiency" improvements.

 

You will lose efficiency by doing anything to most of those motors. You'll get more power but decrease fuel economy, hence decreasing efficiency. Especially if its a non-vtec D-series.

A decent cat and a header will prove to be more efficient.