H3 Alpha high flow or no cat

[SWANK3T]

Any Alpha owners remove the cats or go with a high flow cat? Not seeing much after market and search isn't turning up anything for Alphas that I can find. Truck has been losing MPG and power lately then tried to overheat yesterday when we were sitting in a parking lot, it cooled off after we started moving but that was the first time it's done that, never even got past half way in El Centro! It was around 70 yesterday so should have been fine. Sitting at 115k going to do plugs and wires too.

 

[rsc]

I had a cat melt down on me years ago, never have been a fan of them. Especially now on the computer controlled, modern cars. I say leave the cat off.

 

[SWANK3T]

I had a cat melt down on me years ago, never have been a fan of them. Especially now on the computer controlled, modern cars. I say leave the cat off.

Yeah they don't really bother me I wouldn't remove a good one but I'm not sure I'd pay to replace them especially here in the Great Free State of Oklahoma! If I was still in Cali I wouldn't have a choice!

 

[amrg]

Let us know what you end up doing, one of my first cats is throwing a code and needs to be replaced and I cant find aftermarket replacement either!

 

[SWANK3T]

Will do!

 

[scoreh3]

Is the Alpha manifold like the I5 with the cat built in ? Magnaflow makes free flowing replacements cats and a much nicer free flowing manifold too ( at least for the I5 ) .

 

[06 H3]

It is not, the alpha manifold does not have the cats attached to them

 

[alrock]

I know one Alpha owner that has cut out one cat on each side for a better sound. The Alpha has two cats per exhaust bank, right? If I recall correctly, the Alpha only uses O2 sensors before/after one cat, not both, similar to the 07 and later I5s.

 

[amrg]

Thats true! The first CATs have the sensors before and after. The second CATs aren't monitored.

 

[SWANK3T]

Yes only the first cat is monitored I'm got the bank one code today so I'll be doing this very soon I'm thinking about just cutting out all the cats and just going right back to the gm performance (borla) cat back. Anyone know of any issues? What do I do with the O2 sensors? Can pcm tune out that check engine light?

 

[650Hawk]

This got me curious about my Alpha ('08). It has an aftermarket exhaust with twin exhaust tips. From the engine, of course there are the first two cats (one each side), then the pipes come together right behind the front passenger seat. At that point, there is a single unit, not sure if it's a cat, about 16" long and maybe 4-5" diameter (shaped like an old school cherry bomb muffler). Directly after that is a single conventional shaped muffler that says "Wicked Flow" on it. The muffler has a single inlet and 2 exits; with 2 separate pipes all the way to the back with two oval shaped chrome tips under the rear bumper.

"Wicked Flow"? Anyone ever heard of this system? Good, bad, indifferent?