the car runs strong but I hear a slight hiss at low RPMS. I can't really tell if it is a leak or just my open element/new air flow. I don't always hear it. I think it could be the collector gaskets that came with the kit. (the really crappy ones). I used percy's dead soft header gaskets and I am prett sure it is not those.

 

From my experience, an exhaust leak sounds more like a "tick" than a "hiss".

 

It is a wierd sound to describe. It's like if you made THHHHHHHHHHHHH sound. it almsot sounds like knock but it isn't because it is constant and well its just not knock. I can't say that I like the sound. I plan on replacing the collector gaskets anyways with better ones.

 

From what you describe, I would have to say that it is not an exhaust leak. As johny said, every exhaust leak I have ever heard, even the smallest ones, sound like a tick. Actually, the first time I had an exhaust leak, I thought it was a rocker arm that was loose.

I would take a look at your intake setup. Start the car and get close to where the air is actually entering the system and see if you can hear it. I have a ram air setup that starts behind my fog lights and when the car is running and you are standing in front of it, you can hear a hissing/sucking type of noise. You said that it was making that noise constanly, but does the noise increase in pitch with the engine when it is revved or anything like that? I hope that helps to get you started.

Matt

 

ahh you would know if it was a exhaust leak.... if it dosen't sound like a wet fart and you dont feel any air around it your'e ok.....

 

The noise increases when RPM goes up. I don't hear it at idle but more so after 2000 RPM when I give it decent gas. It almost sounds like a super charger whine, but deeper. Honestly I don't think it sounds good at all and liked the sound of my old exhaust manifolds with the hooker cat-back. It wouldn't be the new cat or anything would it. I also let the car idle and got down and tried to listen to the collectors. I couldn't really hear anything over the rubmle of the exhaust. I am almost positive it isn't a vacuum leak or anything because the car runs okay and idels smooth. It does hang at like 1000 RPM when I push the clutch in at crusing speeds but I just figure that is the car getting use to the headers. The noise I hear couldn't be a stream of little ticks that are so close together they sound like a constant noise, could it?

 

what makes you sure that a car wont run and idle smooth with a small vacuum leak.

 

My open element makes a kind of hissing noise from the air rushing through it.

 

I know its not the open element noise. The headers do cover up that sound and I kinda miss it. On the vacuum leak, I will have to check. I have had many over the few years that I have owned the car so I know what the symptons are. I am not rulling it out but I don't know why I would hear it now and not the last day when I had my exhaust manifolds on. Oh and the car is just as quiet. The car almost sounds the same so its not like the headers made the car a screamer.