catted downpipe or no cats??
#31
Registered User
Thread Starter
iTrader: (17)
Join Date: May 2007
Location: FatLaCe
Posts: 3,395
Car Info: *WiDe AnD LoW*
yea, that's the report I read from cobb that got me double guessing myself. if I did go catless, u think a good protune might be able to fix the overboosting/boost spike issues? I might have to get in contact with GST about this.
#32
VIP Member
iTrader: (17)
Join Date: Jul 2004
Location: Northern California
Posts: 3,969
Car Info: 04 STi
IMHO, it doesn't matter. The gain for catless vs catted is 1-5 whp... not a big difference.
Take it for what you will: I made 271 AWHP and 308 WTQ with a high flow catted DP:
https://www.i-club.com/forums/vendor-tuning-service-parts-review-152/1-ed-eq-tuning-176397/
Those are the charts.
Take it for what you will: I made 271 AWHP and 308 WTQ with a high flow catted DP:
https://www.i-club.com/forums/vendor-tuning-service-parts-review-152/1-ed-eq-tuning-176397/
Those are the charts.
#33
Registered User
iTrader: (46)
IMHO, it doesn't matter. The gain for catless vs catted is 1-5 whp... not a big difference.
Take it for what you will: I made 271 AWHP and 308 WTQ with a high flow catted DP:
https://www.i-club.com/forums/showthread.php?t=176397
Those are the charts.
Take it for what you will: I made 271 AWHP and 308 WTQ with a high flow catted DP:
https://www.i-club.com/forums/showthread.php?t=176397
Those are the charts.
#38
Registered User
iTrader: (25)
Join Date: Jan 2005
Location: Kansas - BAIC 4 LIFE!
Posts: 12,775
Car Info: 04 Forester XT/96 Brighton Project
Well I went catless for these reasons:
- I'm an older body style so I don't get noticed
- It was MUCH MUCH cheaper to get a catless dp vs. a catted dp
- I didn't care about smog so I decided I was going to kill the earth with my car
- Since it was cheaper and would make a few more ponies...why not. I could always put my 3rd cat in since I have a 3rd cat eliminator so I always have a choice when I feel like it.
I think that if you're concerned about the "catless smell" then get a catted version. I've had a Helix catted DP and now a Stromung DP and prefer the stromung
- I'm an older body style so I don't get noticed
- It was MUCH MUCH cheaper to get a catless dp vs. a catted dp
- I didn't care about smog so I decided I was going to kill the earth with my car
- Since it was cheaper and would make a few more ponies...why not. I could always put my 3rd cat in since I have a 3rd cat eliminator so I always have a choice when I feel like it.
I think that if you're concerned about the "catless smell" then get a catted version. I've had a Helix catted DP and now a Stromung DP and prefer the stromung
#39
Registered User
iTrader: (9)
Join Date: Mar 2006
Location: Bay Area, Ca
Posts: 1,257
Car Info: 07 STI
On my old '02 wrx you could just slap on a catless downpipe without EM and be fine, but its just not as easy as it used to be.
-John
#40
Registered User
iTrader: (25)
Join Date: Jan 2005
Location: Kansas - BAIC 4 LIFE!
Posts: 12,775
Car Info: 04 Forester XT/96 Brighton Project
I have read nearly every thread on the interweb pertaining to this issue..it cannot be tuned out as it's also stated on cobbs website. If you do go catless at the very least get a larger restrictor pill, although this isn't a sure fix.
On my old '02 wrx you could just slap on a catless downpipe without EM and be fine, but its just not as easy as it used to be.
-John
On my old '02 wrx you could just slap on a catless downpipe without EM and be fine, but its just not as easy as it used to be.
-John
My swap is from an 02 so I was able to run a full turbo-back without EM until I finally decided to stop pressing my luck and get one.
#44
Registered User
iTrader: (8)
Join Date: Oct 2006
Location: BorderJumperEnforcer's momma's house
Posts: 2,506
Car Info: Fast
Catted for sure.
There is no reason to go catless on a daily driver. You will have to defeat a cat efficiency CEL, possible boost spike issues (especially when it is cold), smell, possible cop issues, soot on your bumper....and a greater contribution to the destruction of the planet, which it seams nobody gives a **** about.
negatives: more expensive (usually $100-$150 new), cats wear out EVENTUALLY, and SLIGHTLY less HP. On a stock turbo you will most likely not notice the difference after you set down the dyno sheet.
The way I understand it, the way that protuning can defeat boost creep is by raising the boost close to the level it is creeping to. IE, you creep to 19 PSI, then get tuned to 19 PSI = problem solved. This is assuming your setup can safely support the equivalent creep boost. You are not removing the creep, just working around it
There is no reason to go catless on a daily driver. You will have to defeat a cat efficiency CEL, possible boost spike issues (especially when it is cold), smell, possible cop issues, soot on your bumper....and a greater contribution to the destruction of the planet, which it seams nobody gives a **** about.
negatives: more expensive (usually $100-$150 new), cats wear out EVENTUALLY, and SLIGHTLY less HP. On a stock turbo you will most likely not notice the difference after you set down the dyno sheet.
The way I understand it, the way that protuning can defeat boost creep is by raising the boost close to the level it is creeping to. IE, you creep to 19 PSI, then get tuned to 19 PSI = problem solved. This is assuming your setup can safely support the equivalent creep boost. You are not removing the creep, just working around it