And there is this hissing sound that everyone was talking about when we were still on H-A.net I can't remember what was said about the sound. Can anyone please refresh my memory?

1) Will the sound go away in time?
2) Is the sound normal?

PS if you are interested in my opinion of the headers, my response is that I can't feel any difference. BUT, I am not one to be very sensitive towards minute changes so don't bank on my feedback.

Once again, thanks for any input.

 

The hiss is there to stay. Learn to love it... But I only hear it above 6krpm. Is that the same? I believe it has something to do with the header thinner walls.

And don't worry, I would not have noticed improvements either if I hadn't measured.

 

Well given that the headers are brand new they take a day or 2 to "break in" That hissing sound is the seal between the cat and the new header. Once the header gets nice and hot the donut will seal up. Im sure that the header to the block is sealed.

I would say run it hard for 2 days and then see if you feel a difference. Try running the car around a corner at a lower speeds then normal in 2nd gear and see if it pulls better down low.

 

Ok, I may not feel any increase in power but I can say that it is definitely lighter than stock. When I put my stock header into the box that the Mugen one came in, I was surprised how much more it weighs.

Before you all start worrying about the weight distribution, let me tell you, the difference is so small that it wont change the front/back weight bias. And the car is not "perfectly" balanced to begin with.

 

Now I am concerned. My car is certainly louder after installing the Mugen Headers.

I do not notice anything till Vtec engagement, but from then onwards you wonder whether you're about to take off.

For those that have installed these headers, does this sound familiar? Or should I look for leaks?

 

I would look for leaks! Take some baby pouder and blow it near the seals. Or you can use your hand. This way you can see if there is a leak. You can also look for any signs of black from the engine.

I heard the car get a little higher pitched. I heard more of a swoosh sound past 6,000 from the headers but it was passenger side foot well. That part was obvious.

 

How much was the headers? And is it worth it?

 

There is a group buy now at the parts counter forum. Its cheaper by about a hundred bucks.

Whether it's worth it is another issue. Basically it is next to impossible to get any improvement out of the car as it is really tuned. Most people here modify their cars because they love their cars and want it to be better. If you expect normal noticeable gain compared to other cars, you will be disappointed.

That said, the Mugen headers is believed to be the best header for the S2000 according to the majority of members on this forum who have done mods.