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.

 

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.

 

haha you could of made 276!

 

Yah go catless get tuned call it day.

/thread

 

lol, it wouldn't matter - won't notice the 5 hp difference.

 

I also make good power with hi flow cat.

 

braggin rights!

 

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 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

 

Yep... the 02-03s are great for that
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.

 

catless for life baby!!! help contribute to global warming!!! My perrin downpipe is,

 

I'm catted =)

 

I think I just saw you on Tassajara/Santa Rita Rd. at about 2:30pm.

 

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

 

aghhh damn, now im unsure...how bout someone buy me either a catted or catless DP and surprise me?