Hello all. I have a 03’ STR.
I’m looking for anyone who’s fitted high flow cats, preferably from Swallows Racing or Paramount performance/VEIZU Performance. Seems like I can’t find any testimonials to these specific companies. These cats are highly expensive and the lack of reviews makes this purchase hard for me to stand by.

I truly want high flow cats because I know I’d love the improved sound and supposed performance. Our ECUs would supposedly need to be bench tuned since through the OBD port doesn’t work. Meaning I’d have to take mine out (Not a big deal) and send it out. Which I don’t mind doing. I’d like to know is the tuning after high quality high flow cats being installed necessary? Can I get away with just the purchase of the cats and no tune? Does the lack of a tune ACTUALLY limit the total performance m you’re supposed to get out of the upgrades.

I have a smaller pulley and cold air intake, the pulley I’ve 1,000% noticed a difference with. The Cats are in questions in relation to the tune because I’ve been told the tune specifically has been barely noticeable or not worth it. I believe tuning the ECU just to avoid a CEL is more than enough