To Fit Ansa Resonator to Stock Headpipe, You May Need Sealing Ring 18 11 1 723 721

[thehackmechanic]

I just submitted this as part of my weekly Roundel Online column, but I thought would be valuable to post here.

 

I went to replace Louie's rotted exhaust with the new Ansa "standard" exhaust I bought from JC Whitney on eBay. I first installed the used OEM headpipe I had kicking around the garage, hung the new Ansa rear muffler, slid the end of the new Ansa resonator into it with one hand while holding up the front of the resonator with the other, slid the sealing ring between the flared faces of the headpipe and the resonator, and was about to start to bolt the flanges together when I noticed something.

Or rather, I didn’t notice something—the sealing ring. It wasn’t peeking out between the flared ends of the pipes like it’s supposed to. Had I dropped it?

I separated the flared ends and verified the sealing ring was inside. I again pulled the flared ends together, and again, rather than the sealing ring sitting between the flares, the flares engulfed it.

What the…?

On close inspection, although the mating flanges and the flares appeared to be the same size, the flare on the front of the Ansa resonator was deeper than the one at the end of the OEM headpipe, and the difference was enough that the sealing ring was completely swallowed as opposed to being trapped between the flare faces, meaning it couldn’t do its job of sealing.

I looked online. Ansa makes a headpipe for the 2002. Was their exhaust not compatible with the stock headpipe? Was I supposed to buy their headpipe to go with the resonator and muffler? It seemed surprising. I also found that there is an Ansa part number for their sealing ring, but like the issue I mentioned last week with the clamp required to attach the resonator to the muffler, these parts from Ansa appear to be NLA. At least they don’t show up on the sites that sell the muffler, resonator, and headpipe.

I thought, well, there are two options. I can either grind down the flare until it’s the same depth as the one on the headpipe, or I can try a larger sealing ring. I elected to try the latter first, as I was concerned that I could ruin the resonator by grinding too much off the flare.

The stock sealing ring is 47mm in diameter. I looked online and discovered that part number 18 11 1 723 721 is 48mm, and thicker. Eight bucks and three days later, I had it in my possession. As you might imagine, being larger, it rode more on the front of the flare rather than inside it, but it seemed like it would work.

 

 

 

I tightened everything up, held my breath, and turned the key.

Blissful quiet.

I put my gloved hand over the tailpipe. The exhaust was tight,

 

 

--Rob

 

Edited March 31, 2017 by thehackmechanic

[HBChris]

The large one looks like M30 where it slips over the pipe.