I'm thinking about purchasing some metallic HFCs. From what I have read most people say they only last around 20K miles, while the stock cats are good for at least 100K. Is this only with FI applications? How long should I expect a good pair to last on an NA G?

 

It all depends on hos modded you are. They can last just as long, if the car stays stock - I said CAN.

The more you mod, the more you have to tune for greater performance rather than that and a combination of fuel economy - typically meaning the car will always run richer once tuned. Excess fuel and possibly blow by oil, is what kills all CATS.

Rick

 

Thanks, however I want to go FI later down the road.

 

Which is why you would go with Metallics or testpipes...

 

Yes metallics if I do for sure. I was catless on a wrx once, horrible smell almost choked me.

 

they should last around 50K miles

 

"Last" what do you guys mean by that? whats signs of your cat's needing to be replaced?

 

The honeycomb inside will clog it up if it becomes loose inside because of X reason/s . I know that usually FI set ups have Test pipes because of the higher fuel mixture being thrown out since they would rather run rich than LEAN! When it starts getting clogged then there goes the inside honeycomb and it gts pushed tothe end of the cat and you got clogged exhaust air which cant escape..... Not good, I was looking into the Kinetix HFC's and poeple say it should be anywhere between 35k-50k before a problem arrises with my mods.....

 

Just another note:

These cars put out a lot of blowby for FI especially. oil does not get burned up in a CAT and will destroy it...pretty quickly I might add.

Also - the reason a rich mixture kills a cat, primarily, is that the excess fuel will cause the CAT to overheat. It will get much hotter when igniting the fuel it traps. This is what mostly causes the breakdown and results mentioned...

 

So, if I'm going to go FI down the road it would be better to go ahead and get resonated test pipes? Idk about risking the felony violation again; plus emmission laws are starting to get a lot tuffer everywhere. I heard the fine if caught is 10K.

 

The fine depends on the state you are in... In Florida its $5k minimum

 

I'm going to be moving to Florida in a few months. I'm sure I could find a shop that would pass me, but what about cops checking?

 

LOL, there are no emissions in Florida.

 

I thought they recently changed this or were planning on changing it and going ODBII?

 

Case in point...

On the bright side, paying $500 for new HFCs will probably be the least of your problems if you go FI.