I have been getting requests to make an off-road H-pipe for the W211.

The H-pipes will replace stock catalytic converter assemblies, both front and rear, and will be a simple bolt in.

Without the cats, you will turn on CEL. However, we can turn it off through software.

Theoretically it should fit CLS55s and E/CLS63s as well.

I need feedback on which steel to use - aluminized or stainless. This choice will determine final pricing, as I am working on the quote.
Please feel free to post your opinion.

 

I'm just guessing, but I would think there are vastly more installed shorty headers installed out there than either mid-length or long tube headers (which are normally sold as a full kit anyway). So I think you should determine interest in two possible configurations.

Both would bolt up to either the the stock manifolds or any of the various shorty headers out there. Both would be stainless since that's what the factory exhaust is manufactured from.

The first configuration would include larger diameter mandrel bent tubing and 100 cell high flow cats in the stock location, and would step down to be direct bolt-ons to the stock exhaust system at the location immediately ahead of the resonator. This would cover those that want to retain installation of the factory O2 sensors and have at least minimal catalysts for environmental reasons.

The second possible configuration would be identical, except it would be a true "off-road" or "test pipe" that would just be larger diameter, same shape except without the catalysts. These would be the hard-core pipes for those that aren't concerned about CELs and emissions issues. That's my fifty-five cents.

 

Hey Vadim, I would definitely be interested in one also. I say go with stainless.

It would be nice to have one with high flow cats with the ability to swap out the cats with "off-road" pipes.

 

go whatever is the cheapest...... I take one also...

 

What would be more important - price (with cats or no cats) or longevity (as in stainless vs. aluminzed)?

 

HAHA!!! Both!! How about cheaper stainless?

 

IMHO it should be stainless with no consideration for aluminized. Just get a lower grade stainless (eg: Not T-304) and you'll be fine.

Good call on offering the H as an option, although I prefer the sound of an X-pipe.

Thanks,
Brad

 

So 409 with X-cross is the winner.

We are working on it. I will post some pixs later.

 

Forgive my ignorance, but this can used in place of the secondary cats and would not result in a CEL correct? And removal of the secondary cats might also increase power...ever so slightly along with a little bit more rumble?

 

Removal of the secondaries does not illicit a CEL. Power gains or losses are arguable.

 

That is what I thought...does this piece go in its place?