Lowend

iTrader: (5)

Heedz - I'm not trying to fight with you... and I don't think we disagree all that much on is.

The Vette statement is relevant. Airflow is airflow. If a 3" cat has the CFM to support 600HP from a Corvette, it has the CFM to support 600HP from a Subaru.

The point of the intercooler isn't to allow air-flow, it's to transfer heat. While the stock unit may allow enough air through it to support x-amount of horsepower, cooling effects can no-doubt be improved.

The AVO downpipe brings up in interesting question: Does the EO# for the cat apply to the whole assembly? I tend to think "no". Since the majority of the downpipe is upwind of the cat, the tubing is technically subject to it's own smog regulations. I don't know if anyone would care.

Heedz

iTrader: (51)

Pretty sure its the cat but, if a cop see's a carb sticker for it, usually they won't do much about it unless they're really into cars aka Rosetti probably wouldn't give a rats *** about it.

The cooling of the stock intercooler is more sufficient because of the dam thats on your hoodscoop vent, hence why the stock has a bit of an encavement on it. The splitter is meant to fit into there, like how for the Legacy the engine cover directs flow to the intercooler.

I'm just trying to prove my side with valid points, trust me if you've seen me argue you'll know instantly lol.

NorCalSTi53

ok...still undecided, im going to bolt up the P&L im picking up tonight...and try to gauge how loud it will be before deciding betweed catless or catted...f*** im turning this into a bigger decision then it needs to be!!!

slugrx

iTrader: (12)

i never wanted to deal with DP problems so i got myself a catless sti uppipe for a little more spool and to blend in on visual smog (you already catless there) and a straight pipe catback for noise

im loud as hell but if i were to be pulled over, ive still got my stock dp, they would never see the uppipe (even if they did its in oem subaru heatshield) so i wouldnt have any problems with ref, just a fix it ticket at the most

i did however get a cobb ap to flash stg1 cuz the stock tune is crap, i might get a protune stg1 but i like having the AP to check CELs and being able to clear them

plenty enough power for me, ive hung with and have taken more powerful cars on 17 because of better suspension upgrades and tires

herrjr

iTrader: (12)

I guess this is what AVO did. Hmmm, too bad there hasn't been one done yes for the GR/GVs.

flat489

iTrader: (7)

you want to stay safe? stick with the OEM dp for a little while. Before people jump down my throat there is info showing that the newer downpipes are in fact less restrictive than ever before. The jump to catless or highflow catted isnt as signficant. I belive the test was done by either COBB or PERRIN, one of the two. But yea just flash to stage 1 with a cobb ap, get a catback and enjoy life for a bit. You can even add an intake, again for a GR/GH this will add some power. It does decrease the tq by a slight amount however.

I ran catless before with my bugeye and will be running either an Invidia or Cobb catted dp next.

Heedz

iTrader: (51)

facebooked you herrjr

aboothman

iTrader: (8)

Or you can run a gutted stock downpipe I would like to see a bell mouth that can be hidden be stock heat shields and bolt to the gutted cat sections of a stock downpipe

Manny408

iTrader: (1)

Electric Exhaust Cutout ftw.

Heedz

iTrader: (51)

How are you going to avoid cats or swap downpipes that has nothing related to it? More so for catbacks..

SeaOfGreen

I'm have a exhaust cutout with 3.5" APS downpipe and midpipe V-banded to stock muffler. The Plus is I don't lose power and when I need to be quit I can and still look stock. Problem is no matter what if that cop is a dick he's going to pop his head under the car and find it no matter what, just hope you don't run into a dick cop.