Gutting out the stock cats

[diss7]

Originally Posted by wparsons

Why not just get a proper pipe with a high flow cat??? There are more gains from the larger piping than from punching out the cat in the front pipe.

The stock pipe is like 2 1/8", a 2.5" pipe with high flow cat will make more power across the rev range than the stock pipe with a gutted cat.

That would mean replacing all the piping, something I don't want to do.

[wparsons]

Why not? Replacing the midpipe is dead simple, it's like a 30 minute job working slowly without a hoist. It's only 5 bolts to replace the midpipe, two at each flange and one hanger.

[diss7]

Originally Posted by uspspro

It's not free. Since one would be destroying some expensive parts.

The OEM cats are worth a bunch of money. Look up how much they cost new.

If you really want to go catless, keep the OEM stuff in a bin, get a header/test pipe. In a couple years when someone buys a ghetto mod'ed FRS for cheap, they will pay a good price for a set of OEM cats, especially in CA.

I don't buy into this. There are plenty of people already who have replaced the stock exhaust because they are convinced it is rubbish. You could quite easily pick up a used stock exhaust system from people like this for next to nothing.

[diss7]

Originally Posted by wparsons

Why not? Replacing the midpipe is dead simple, it's like a 30 minute job working slowly without a hoist. It's only 5 bolts to replace the midpipe, two at each flange and one hanger.

Two reasons; one I don't believe the gain/cost is worth it. Two, as I've said numerous times now, I want to keep the car looking unmodifed.

[WolfsFang]

Originally Posted by wparsons

^^ This! I bet an OEM front pipe with cat is worth about twice what a catted aftermarket front pipe is.

I know on some VW's the much smaller cat pipe is like $900 from a dealership for a cat with two flanges.

LOL you would be lucky to get $100 for our cats. Who would want to buy our OEM cats for more than $200? Anything higher you can just get a aftermarket mid pipe with a cat. Only people who I see buying them are people who want to revert back to stock. A junk/scrap yard will prob give you $50.

[wparsons]

Originally Posted by diss7

Two reasons; one I don't believe the gain/cost is worth it. Two, as I've said numerous times now, I want to keep the car looking unmodifed.

Then don't modify it... gutting cats is IMO a ghetto solution. You're not going to see any useful gains from it.

Originally Posted by WolfsFang

LOL you would be lucky to get $100 for our cats. Who would want to buy our OEM cats for more than $200? Anything higher you can just get a aftermarket mid pipe with a cat. Only people who I see buying them are people who want to revert back to stock. A junk/scrap yard will prob give you $50.

Junkyards here will pay well over $100 for a rusted out old cat from a 20 year old car, so they'll definitely pay more for an almost brand new one. The metals in them are worth quite a bit for their size/weight.

[diss7]

Originally Posted by wparsons

Then don't modify it... gutting cats is IMO a ghetto solution. You're not going to see any useful gains from it.

As posted above, another user has seen gains.

Unless you have your own information contradictory to the above?

If it shows gains, fits in with what I'm trying to achieve, and costs nothing, then I don't see what the issue is.

[WolfsFang]

Originally Posted by wparsons

Then don't modify it... gutting cats is IMO a ghetto solution. You're not going to see any useful gains from it.



Junkyards here will pay well over $100 for a rusted out old cat from a 20 year old car, so they'll definitely pay more for an almost brand new one. The metals in them are worth quite a bit for their size/weight.

dam maybe i should drive up to you, over here they wont give me crap for my catted front pipe.

[NickFRS]

In oregon it's illegal to sell cats that are used..... No one wanted to buy mine anywhere.... So anyone have anymore info about this? My cousin is currently gutting my header cat and replacing my front pipe cat with a pipe.

Wondering how the power will compare to the RevWorks UEL header w/Nameless 2.5 Front Pipe w/High Flow Cat that was just on the car.

When he guts the header cat he is going to shave the inside and polish it... Also going to polish the ports on the head and maybe enlarge them a tad. He is also removing the stock resonator.

I have the 3in nameless mid pipe to dual 2in cat back proto... It was actually quite quiet with the cat less header and high flow cat. So wondering what it will sound like now... If gains are close to the same i'll be surprised. When the 3in pipe splits to the dual 2in there is a resonator in each pipe... Then it runs to two mufflers out the back... So I don't mind running catless... Also around here anyone would sell a stock exhaust for dirt.

Going to be a fun experiment.

My car also has a Innovate charger.... Made 240WHP 200WTQ before.... So will be interesting to see what it after the Gut + pipe replacement. Oh. He is also doing it so all the stock shielding will remain on the pipes.

Also getting a de-fouler for the header. Going to test if it works.

[WolfsFang]

Just to ass to this our cats dont have rare metal in them so they are worth close to nothing.

[ZionsWrath]

Originally Posted by diss7

There is one in the header, one in the front pipe. Removing the one in the header causes issues, as there are sensors before and after the cat, that will then think there is an issue and throw a CEL.

There are ways & means around this CEL, but there is mixed reviews on the success of these methods. Of cuorse you could get a flash/tune to solve this.

The one in the front pipe is not measured in this way, and can be removed without issue.

I'm all about keeping my 5 year warranty. Also, we have to get our cars inspected yearly, and they love failing modified cars.

What do the turbo guys and people who replace header do?

[liquidsky44]

Originally Posted by diss7

Two reasons; one I don't believe the gain/cost is worth it. Two, as I've said numerous times now, I want to keep the car looking unmodifed.

I had the same reason for doing this as well. Overall it works somehow. The gain is there after proving it with a stock 86 on the quarter mile. Beat him by at least 2.5 car lenghts.

[ML]

Originally Posted by NickFRS

In oregon it's illegal to sell cats that are used..... No one wanted to buy mine anywhere.... So anyone have anymore info about this? My cousin is currently gutting my header cat and replacing my front pipe cat with a pipe.

Wondering how the power will compare to the RevWorks UEL header w/Nameless 2.5 Front Pipe w/High Flow Cat that was just on the car.

When he guts the header cat he is going to shave the inside and polish it... Also going to polish the ports on the head and maybe enlarge them a tad. He is also removing the stock resonator.

I have the 3in nameless mid pipe to dual 2in cat back proto... It was actually quite quiet with the cat less header and high flow cat. So wondering what it will sound like now... If gains are close to the same i'll be surprised. When the 3in pipe splits to the dual 2in there is a resonator in each pipe... Then it runs to two mufflers out the back... So I don't mind running catless... Also around here anyone would sell a stock exhaust for dirt.

Going to be a fun experiment.

My car also has a Innovate charger.... Made 240WHP 200WTQ before.... So will be interesting to see what it after the Gut + pipe replacement. Oh. He is also doing it so all the stock shielding will remain on the pipes.

Also getting a de-fouler for the header. Going to test if it works.

This is what I want to do as well with the mid pipe and header. Please keep us updated.

[BlueDubbinTDI]

Can't you just swap back to the stock pipe before going back to the dealer for anything to avoid the warranty hit? I feel like they wouldn't even notice and even if they did catch the smell left in your catback they can't prove anything right?