CataclysmGT

I just installed a pypes O/R h pipe yesterday, and I am certain I have an exhaust leak. Sounds like its mid car, at the H pipe / before axle pipe connections (via clamps). I did look today when I started her up, and there was one drop of water at those connections.

How likely is the crossover to leak? Its a pretty damn tight fit putting the one side into the other.

Anyhow, I am lifting the car this evening to take a look. Any helpful hints would be appretiated.

Cheers

howarmat

I noticed the same sound when i put my o/r h pipe on....there are no leaks that i can find though. I think its just the better flow air flow that we here.

Derf00

There is some stuff called Exhaust sealer (Autozone) that comes in tube. It's a silica or carbon silicat based material that's designed to seal that kind of stuff. It can handle exhaust manifold/header temps. I used that at all joint joints (compression or clamped) when I put my exhaust system in. Zero leaks.

thewarmachine

Hey, Cat, I heard that noise too last week when I had the Pypes O/R H-pipe on. That's the one sound I didn't like....sounded like a clunker from inside the cab until you got a few rpms higher, then it trumpeted loud. I prefer my stingers to be smooth sounding.

CataclysmGT

Yeah, if I cant contain the leaks by adjusting / reclamping.....ill be using some sort of sealer to get rid of that tinny noise. As far as I can tell, there are no leaks at the headers........which is good.

bigherm00

Just a few days ago I noticed a little sound that others think is a small exhaust leak. My exhaust was converted to duals (I have a V6) over a year ago and I just noticed the sound within the last few days. But, I only noticed it because the window was down and the radio was turned down as well. It sounds kinda like a little whistle, and you only hear it while idling and when I barely rev it, it kinda whistles when the rev is coming back to idle. You suppose that is in fact a little exhaust leak? All of my exhaust is welded rather than clamped, but I dunno, I suppose a hole can develop somewhere.

I also just noticed a noise under the hood too. It's a similar sound directly from the top of the engine, but you can't drown it out with ambient sound with the hood up. Friends think it might be a lifter, so when I get my pickup back, I'm takin the car to the dealership before my warranty runs out. Still have 5k left on it, so I hope I get it up there in time.

CataclysmGT

I don't think its a hole, I think its a leak past the clamps. It sounds pretty tinny....like an exhaust leak. So, I presume its an exhaust leak since I just installed a new exhaust component. Ill find out it 20 minutes here.

FyouGitive

When an exhaust valve closes the sudden cnange of pressure sends a sound shock wave down the pipe. The reason you bought headers was to "tune" the position of that shock wave so it didn't interfere with the orderly procession of such shock waves down the exhaust column, or to enhance the extractor effect. Winding around is not always just to fit the space, it's to achieve the correct length between origin and junctions and exits. It's not easy to discern those waves' sound effects in cast iron headers, but in tubing headers sometimes it sounds like a can of marbles rattling around under the car.

Under other circumstances, a sound you're not used to may suddenly be very noticeable, and some of those exhaust pulses are likely creating standing waves and sound in a pipe when the engine is not accelerating or slowing down.

When I was a lad, we had two tests for exhaust systems: if we flicked the tip with a middle finger and the metal rang like a bell, it was good; if when the engine started and idled we could hear the "tink" sound, we nodded wisely and said, "headers".

Some of the neatest exhausts ever were the "crossover" headers that merged selected tubes from opposite banks of V-engines, making the system a whole that included all cylinders. A few Trans-Am racers and NASCAR racers used these, as well as some Formula A/5000 cars. Big old thumping V8s that sounded like angry giant bees. Cool.

Ain't science wonderful?

holdstill79

I also have an "exhaust leak" type of noise which seems to be coming from under my feet (where the o/r H-pipe meets the header) The best I can explain it is like driving a mid 80s ford pickup that had a faint "tick" when picking up speed. When my windows are down all I hear is the sweet sound of 8 cylinders and the neighbors screaming. With the windows up, it is awful. I am going to do a recheck on all the clamps. If anyone has a fix without having to take this all the way off again, please let me know.

CataclysmGT

Well, had the car up, and can for sure hear / and feel a leak at the H pipe halves connection. I tried to push the two together more, but hardly had any movement. For whatever reason, there is a slight tweak and the pipes kinda bind against each other. This, of course, causes massive friction when trying to move them. I have like a 3.25" space between the pipes, vs 3" for the stock H pipe.

I also had a water stain on the downstream side of each midpipe / axle-forward pipe. I tightened those a lot more......so they should be good.

I will be calling a muffler shop to weld together that H pipe connection, and to check for leaks at the header pipes (though, as far as I can tell those are not leaking)



On another note, the Brenspeed tune is excellent for speeding up throttle response. 5th gear is still gutless.......can't really tell if its better or worse. Might go throw it on a dyno soon just to check the a/f ratio and rwhp and make sure there is no "bogging".