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Old 01-01-2003, 07:58 PM   #1
Scooby Newbie
Member#: 30550
Join Date: Nov 2002
Location: Ottawa, ON
02 2.5RS
platinum silver

Default headers + high flow cat worth it?

Ok 5 spd 2002 2.5RS with:

BRullen catback
PRM/Cobb intake
Cobb street cams

I want to go faster. Don't want to weight reduce however.

I was thinking of selling the brullen catback and just putting in the MRT system since it seems to be the only one i can find with numbers to back up performance claims. Otherwise i'm tempted to wait for the Cobb headers to come out.

Will headers & high flow cat help my current setup enough to make it worthwhile financially? That is will i get at least 10 more hp by adding them into the equation? Otherwise i can't justify it.

What about pullies?
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Kazushi is offline   Reply With Quote
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Old 01-01-2003, 08:47 PM   #2
Scooby Newbie
Member#: 17178
Join Date: Apr 2002
Location: palo alto, ca
2001 2.5RS Coupe
Silverthorn Metallic


i dont know if it will give you "at least" 10 hp but i know that when you (if you) get the headers, along with everything else you have, you will have a complete free flow system. right now your stock headers are restricting the airflow so once you put in the new headers you'll be free flowing (headerback). this should free up some hp but as for how much? it varies. some choices for headers are:

mrt headers (w/ or w/o cat)
borla - great sound not much pound
twe - heard good things, not many people have tried
brullen - i dont know

theres probably more out there i just cant think of them. hope this helped and good luck.
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Old 01-02-2003, 12:03 AM   #3
Scooby Specialist
Member#: 420
Join Date: Oct 1999
Chapter/Region: SCIC
Location: The LBC, CA, USA
2001 Cr-V


I'll give you a qualified yes - Qualified in that I noticed a nice power boost by adding a hi-flow cat to stock headers / strohmung intermediate and Sti rear section. I don't really know if the ID of the headers is a real restriction, since the shape of the tubing paths is enough of a problem. With all of your other mods, I'd say you'd notice a big boost by removing the one remaining bottleneck in your system. Cobb is supposed to be releasing it's header/cat combo, and I'd look for some type of combo system, if not that one. I'm still wrestling with the decision to buy headers, give the CEL problems, and the lack of evidence that they satisfy in the dollar/hp category. If I could get a deal on borla g4s, I might, but I'm not in a hurry, since I know i have to replace my clutch (almost 70k on the stocker), and I'll probably go for a new flywheel at the same time.
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Old 01-02-2003, 08:53 AM   #4
Scooby Specialist
Member#: 6542
Join Date: May 2001
Chapter/Region: South East
1997 Ver IV


yes, i think you'll notice a gain, because you've got cams...cams are the key to taking advantage of all this added intake/exhaust flow, since the stock ones have the profile of a bic pen.
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