If your only option was to retain the stock Y instead of going to true duals, but you were able to swap out cats, would it be beneficial to replace all 4 cats with high flow cats on a 2000 5.4. Looking for a way to open up as much as I can while still retaining the 4 cats and stock Y.

 

Cut the rears out and replace the fronts with highflows.

 

Going to have to retain 4 cats.

 

X2

Or just remove the rear cats and leave the fronts. Just as good as hi-flows, but there is a chance that you will through a CEL.

 

wats X2 mean? an CEL?

 

Here in NY throwing a CEL is not a good thing. I need to avoid that. I finally found someone that will replace cats with highflow versions even though they wont delete them. Im just wondering if there are highflow replacements for both types of cats or only fronts

 

naw i was guna get all highflows from magnaflow but it was guna run 1200 parts only because u have 2 get the front 2 seperaate from the rear 2 very expensive

 

If you have to have 4 cats because of a visual inspection, replace the rear cats with hi-flows. The front cats are more like resonators than cats.

And "X2" means that I agree with the person I quoted.

Ex. X2

 

Thanks 4.6 Thats pretty much the info I was looking for.

and on the boobies issue...X3

 

You don't "have" to have the stock y pipe though... x4 on boobies

 

X5 on boobies!

 

I have yet to find a muffler shop that will reconfigure that Y pipe here. They will replace cats but none of them will eliminate cats or eliminate the Y pipe. If there is anyone on here within a reasonable drive if me Id be willing to take a drive to get it done but otherwise I think my best option here in NY is to just go with the shorties, replace the rear cats, and run straight pipes or a bullet with a Y.

 

I had the exact same problem, the big name muffler shops always said no, especially over the phone. Go to a local shop and talk to the mechanic in person and offer to pay in cash. I was quoted $240 to remove all 4 and replace with 2 94106's. Let him keep the stock cats and knocked the price down to $180. Paid in cash, no receipt, Im pretty sure that transaction stayed off the books. Just talk to them in person at a local shop and you should be good to go. I have the y-pipe, 2 hi-flow cats on my '00 4.6 and it sounds amazing.

 

x6

I'm hoping to do some high flows too. I want some more sound out of mine. Kinda bored with what I have.

 

Sounds like you're from California. I made a thread about taking someone telling my my true dual set up was illegal, but not all exhaust shops are the same. Some are more strict than others.