Hello, so im debating on two different scenarios:

Get a hi flow cat and run on the stock exhaust (would i see any gains?)

Get a cat back exhaust (more money and no hi flow cat)

Would getting just the hi flow cag be worth it and if so any recommendations?

 

A HFC (or testpipe) will show better gains than just a catback. If you insist on using a cat, check out Mil.Spec's 100-cell.

 

So I can run just the cat alone with the stock exhaust?

 

Also do i need a tune to run it?

 

No you don't but you won't get the best gains, probably won't even feel a difference with the mod. My advice is save up a bunch of money for the mods you want, install and tune at once to save money.

 

^^^ Thats my plan but first I need an evo

 

Along the same lines is is safe to run a catback and test pipe without a tune?

 

Probably, why not tune it though?

 

I thought test pipes/HFC would not respond too well without a tune? I thought i read somewhere that it would make the car run lean? or maybe thats the downpipe..

 

No tune because Im low on funds, maybe just get an access port instead, is there an ots tune just for a cone filter?

 

A stage 1 AP OTS map will provide more gains to a stock car than bolting on a testpipe & catback w/o tune. Yes, there is an OTS map you can use with just a filter.

 

[QUOTE=Kracka;9903835]Probably, why not tune it

I want to stay tune free, but I guess I can always unmarry the AP if I need to go in for work. If I was going this route I would just buy the AP now before any other mods.

 

i was so close to doing this, hfc with stock exhaust until i came across the catback i have at a price of a hfc.

 

Which catback is this?

 

I believe the most restrictive part of the exhaust is the cat, but would a high flow cat set off CEL?

I am on the same boat here, I want to get a CBE too, but you probably won't gain much except for sound and look

Does the 2011 Evo has a new stock exhaust that flow better? if that's the case, I may just upgrade the cat...