Stock downpipe cat removal

Hey guys. I’m looking for any info on either gains or exhaust note changes when gutting the cats from the stock dp. I have an ots freektune on the car as well as the e33 tune an while I know gutting the cat will lean it out I’m wondering if the ecu can compensate so I can have my fancy turbo whistle! Also maybe a few tiny hps.

 

I think you have your answer already... I'd that you should get a touch-up tune if you swap on a different down pipe or go from catted to catless and this is the same idea. If you want the best answer for your tune I would shoot freektune an email and then go with whatever Justin reccomends for your car / tune. If you do shoot him an email let us know what he says.

 

Will do boss! Appreciate the answer. Just didn’t wanna get a touch up while keeping stock dp size is all then another when I can afford the better catless version

 

Totally understandable, email Justin and see what he says, he may reccomend a touch-up tune (partial cost of full tune also all you'd need if you added a DP and are already tuned)
https://www.freektune.com/products/mazdaspeed3-6-touch-up-tune

Perhaps some others will chime in here, personally if I was looking to upgrade the DP soon ish I'd just wait it out.

 

Agree with the pain of removing a downpipe I would only want to do it once. Wait until you can get the downpipe you want and pay for the touch up tune

 

If you’re going catless then find an eBay one used on Facebook. Or eBay if they’re in stock but atm I don’t think they are. If you wanna be lame and stay catted then that’s when I’d stick with something like UR or cpe or something

 

Interesting about the ‘turbo whistle’. Is that enhanced by a catless downpipe? When I rebuilt my engine I used a $300 K04 remanufacture (my thought was to use it until I could rebuilt the OEM turbo which was spitting oil, but it’s been totally fine for the last year). Ever since then I hear a whistle sound from the turbo which I never heard from the OEM.

 

It should be enhanced. May need an intake for it

 

Intake with a metal tip is going to make another difference in turbo noise

 

I do have a Corksport intake now as where I had another brand (name escapes me…) when I used the OEM turbo which was longer and extended into the space in front of the wheel well. The wooshing sound was plenty audible with that but there was no turbo whistle.

 

The ko4 doesn't have a loud whistle compared to some of the bigger turbos out there

 

the k04s intake sound is definitely a succccc
My S4 is considerably quieter with a hint of anti surge whine.
S257sxe has a pretty damn loud whine and same with the FP black for Subarus. That’s all my experience.

but pretty much any turbo car with an un resonated/catless exhaust will give you a nice whistle out the back