Author Topic: Ebay Full Length Header? (Read 3486 times)

AcSchnitzer318is · « **on:** July 11, 2008, 11:03:27 AM »

Anyone tried something like this? I have an exhaust header leak that I can not track down and as a last resort was going to switch headers. Replaced all 3 gaskets already, 2 at head and 1 at collector, no luck.

Ebay Header

EN318isPDX · « **Reply #1 on:** July 11, 2008, 11:10:32 AM »

When people look at my factory exhaust manifold they always ask me, wow dude nice header! The BMW factory "header" is the best available for our car.

bmwman91 · « **Reply #2 on:** July 11, 2008, 01:39:01 PM »

The stocker is as good as one can hope to get on an NA motor. If you cannot find the leak, it might be a cracked weld, which is somewhat common. Have you checked the downpipe around the catalyst yet? I had an after-market catalyst welded in and the shop did crappy welds that I had to chase with my own MIG welder. Are you positive that a)the leak is form the header and b)there is a leak at all? The m42 is a tad raspy even without leaks.

Also make sure the flange between the catalyst and muffler section is tight.

Check the exhaust system for black carbon deposit streaks. If the leak is pre-catalyst then there is usually some soot build-up by the leak. I don't know where you are located, or if this car can be out of commission for a while, but I can weld up any small holes you have if you like (I am in the CA Bay Area). I would prefer to do it off-car though lol.

futron.sim · « **Reply #3 on:** July 12, 2008, 07:43:47 AM »

I have bought one of these 4-1 headers on ebay and still waiting for it to arrive.

IMHO, these 4-1 headers are good if you want more top end power and don't mind losing low end.

AcSchnitzer318is · « **Reply #4 on:** July 12, 2008, 02:48:15 PM »

Quote from: futron.sim;53181

IMHO, these 4-1 headers are good if you want more top end power and don't mind losing low end.

I'm not really looking for any performance upgrade... just no leaks.

Quote from: bmwman91;53146

The stocker is as good as one can hope to get on an NA motor. If you cannot find the leak, it might be a cracked weld, which is somewhat common. Have you checked the downpipe around the catalyst yet? I had an after-market catalyst welded in and the shop did crappy welds that I had to chase with my own MIG welder. Are you positive that a)the leak is form the header and b)there is a leak at all? The m42 is a tad raspy even without leak.

LOL I'm in SA, TX so that wouldn't work. I'll try to tighten the collector nuts some more, but I think I tightened them pretty aggressively and no change. I also filled the header with water when I had it off the car to test for water leakage anywhere... and it had no leaks other than the 4 bolts on top of the pipes. What the hell are those for anyway???

Will a bad cat make a sound like this? I might drop the exhaust and inspect the pipes further down the chain. I am having a magnoflow muffler installed soon and want to fix this problem before I have it done.

Quote from: EN318isPDX;53139

When people look at my factory exhaust manifold they always ask me, wow dude nice header! The BMW factory "header" is the best available for our car.

I'd love to keep it... just want to ditch the raspy leak sound.

Thanks for the suggestions guys, keep em coming. I'll check anything you suggest as this rasp is killing me.

bmwman91 · « **Reply #5 on:** July 12, 2008, 11:32:16 PM »

If you have a smaller after-market catalyst installed, it can make things a little more raspy. The M42 just sounds that way to begin with. How badly was it leaking at the 4 plugs on the header?

AcSchnitzer318is · « **Reply #6 on:** July 14, 2008, 12:33:44 AM »

Just a small seeping on of 1 of them. I took them all out and retorque'd them. Didn't want to be too hard on them though because they seemed pretty small and possibly fragile. Maybe I'll tighten those a tad more as well. I'll take a look tomorrow when I lift it for it's oil change.

Can I spray water or something on the header/pipes to check for a leak? Maybe soapy water? I realize this might only work while the exhaust is still cold but at least it would give me an idea.

nicknikolovski · « **Reply #7 on:** July 14, 2008, 03:41:48 AM »

Put a rag over the exhaust tailpipe (not for too long) and see if the exhaust noise and gas comes out directly from around the manifold. It will be the only place for exhaust gas to escape hence presenting you the leak.

redmist · « **Reply #8 on:** August 15, 2008, 01:37:39 PM »

I bought and installed one. Only problem is the end is not 2.25", it's less. I just cut off the part that tapers down and installed a 2.25" pipe OVER it. Fits nice and tight.