Questions about flowmaster 80 series inlet size

[Slam32]

I want to get a flowmaster 80 series, but the one i can get for a good price from a guy has is 3" inlet and 2.5" out. Will this fit with my stock pipes? i dont want to get all new pipes. And is it worth getting a high flow cat? thanks I know this might have been answered before but i did a search and couldnt find an answer.

[Whyildkatt]

Thats the one I got from summit racing for $87 shipped. 3" in and 2.5" out. My stock piping is 2.25". If you take it to a muffler shop, they will be able to put a coupler in there to make the two compatable... i just had it done last week... sounds awesome. Mine is all stock, but hearsay is that if u ger a high flow cat, u will need an o2 sim... 50/50 chance. because your computer does something funky... maybe someone else could explain this better

[shortdog273]

<blockquote>quote:</font><hr>Originally posted by Whyildkatt:
but hearsay is that if u ger a high flow cat, u will need an o2 sim... 50/50 chance. because your computer does something funky... maybe someone else could explain this better<hr></blockquote>

You pretty much said it. I had my highflow cat for about 3 months and no SES light....so far