Stock H-pipe question

So I've been searching and searching for a used high-flow catted H-pipe to buy and cannot find a single one for sale anywhere. I'm starting to think that my search will never find anything useful so I'm trying to come up with other ideas. Buying a new $400 H-pipe isn't an option right now and won't be for a long time. So instead, here's my question:

Has anyone ever looked into having two of the cats removed from the stock H-pipe? Sure, it will still be 2 1/4 tubing instead of the 2 1/2 for aftermarket, but I would think that having 'ol "test tubes" welded inplace of the two forward cats would improve exhaust flow a bit. Given the placement of those cats, is that something that could be done on the car? Or would it need to be removed to reach it? Do you think I would be able to convince a muffler shop to chop out two of the cats or are they going to have an issue with doing it? Any idea if this would give even half the Hp gain of going with a aftermarket high-flow H-pipe?

Thanks!
 
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Were it me, I'd get an O/R pipe and buy two 3-way 50 state legal cats and make a catted H.

Please note that in some parts, it's not acceptable to run fewer than the OEM number of cats, so you might fail the smog test.

The stock cats are fairly restrictive. Some guys have gutted the pre-cats (for off-road use only, of course ;) ) and installed two high flow cats on their stock H.

Random ideas.
Good luck.
 
Were it me, I'd get an O/R pipe and buy two 3-way 50 state legal cats and make a catted H.

Please note that in some parts, it's not acceptable to run fewer than the OEM number of cats, so you might fail the smog test.

The stock cats are fairly restrictive. Some guys have gutted the pre-cats (for off-road use only, of course ;) ) and installed two high flow cats on their stock H.

Random ideas.
Good luck.

I've thought about the o/r + cats thing and it does interest me a bit. I'l need to do a cost buildup of that tomorrow to see what it looks like.

We do have smog testing in my area, but as long as it's passing a quick peek visual inspection and passing the roller test I don't think I would have problems with two missing cats.

Your idea of gutting two of the cats though i hadn't even thought of. With those two front cats so close to the flanges it should be pretty easy to get something in there to ream them. Hmmm, I'm going to have to think on that one. :D Doing that would be the cheapest option for now, just more time consuming for me with the removal and installation of the stock piece.
 
Don't gut the front two cats, you will be sorry. I did and my car sounded like total crapola. I ended up buying a MAC offroad H after that mistake and couldn't be happier. My car picked up some power and sounds awesome now, it really made the car.
 
Me personally....I run a UPR X-pipe and love it. Every 2 years my car has to go through DE inspection. I take the X off and put the factory h back on, run it through and then switch them back. I know it sounds like a big PITA, but, it only takes a couple of hours. I get better mpg with the X too.
 
Does anyone have any sound clips of stock headers, o/r H, and stock catback? If you don't have a clip can you comment on how loud it would be or how much it would drone? I don't want to have any cops poking around under the car due to excessive noise and not find any cats. Also since the car is a vert I do more cruising in it than racing, so drone at cruising speeds would kill the deal for me.
 
I don't have any sound clips but my system on my vert consists of stock headers, Mac offroad H pipe and turbo mufflers. It sounds nice especially with the top down and it's not loud and obnoxious at all. I would think by just changing out the factory H it would be pretty subdued and have alot better tone to it.
 
I've gone ahead and ordered an o/r H. To hell with the polar ice caps, who needs to stop global warming! ;) I'll jest need to swap it out every year for inspections. If I ever get sick of that I'll have cats welded in down the road.
 
I know with stock headers, o/r H, and stock muffler's that it isn't going to be as loud as aftermarket shorties, and flowmasters. You should be happy with the h-pipe and everything else stock. The cops always bother me anyhow. I've been pulled over 40+ times for bull ***** and most of them compliment me on the sound
 
only thing i would have suggested would be a off road x instead of h but im sure you will be a lot happier with the results compared to the stock h pipe lol let us know how it goes.

Yeah, I prefer the muscle tone of an H compared to the (many times) raspy or tinny sound of an X. I know it costs me a little power but I think the tradeoff is worth it.

I had a MRT Catted H-pipe and Steeda cat-back on my old 03 Cobra and it was exactly what I was looking for. Slightly louder and deeper idle, absolutely no drone at cruising speeds, and unleash holy hell at WOT. If I'm luckly maybe a o/r H and stock cat back will get me close to the same this time around on this car.
 
If you live in CA like I do be aware that the CHP has been trained to inspect vehicles for o/r H. I've had three friends ticketed for running o/r H. All of them were pulled over because of the sound of their cars. I run a high flow catted H and I've been pulled over once and inspected but didn't receive a ticket because everything I have is 50 legal.
 
yeah i hated my h so i went to a x...i dont think i could ever go any other way i got people coming up and asking why my stang is so much louder then there? only thing i can think is after the x i had custom bent flowmasters and turndowns? ...i need to change my 94's h pipe....it is basically a 1" off the ground lol i didn't put it on and havent climbed under the car...its winter here lol to cold lol why do you guys suspect it is hanging so low? loose and needs to be adjusted?its the end where it bolts up to the cat back.
 
If you live in CA like I do be aware that the CHP has been trained to inspect vehicles for o/r H. I've had three friends ticketed for running o/r H. All of them were pulled over because of the sound of their cars. I run a high flow catted H and I've been pulled over once and inspected but didn't receive a ticket because everything I have is 50 legal.


what was the fine for not having cats on your friends cars?
 
yeah i hated my h so i went to a x...i dont think i could ever go any other way i got people coming up and asking why my stang is so much louder then there? only thing i can think is after the x i had custom bent flowmasters and turndowns? ...i need to change my 94's h pipe....it is basically a 1" off the ground lol i didn't put it on and havent climbed under the car...its winter here lol to cold lol why do you guys suspect it is hanging so low? loose and needs to be adjusted?its the end where it bolts up to the cat back.

Maybe the hangers aren't attached.
 
i first put a O/R H pipe on my car with stock headers and cat-back. It was a big improvement over stock, but i really didnt care for it too much, just didnt like the sound of it much. since then i put mac headers and flowmaster american thunder cat-back on it...it sounds awesome, i love it. loud, but sounds damn good and not loud enough to be annoying or anything. i wouldnt change anything about it