Stock cat back, junk or good enough?
 

We have very strict dB limits during the track days and might try to make power on the stock cat back.

Anyone making power with longtube headers, cat delete and stock cat back? Better to find a aftermarket catback with big/effective mufflers?

I'm not sure how much power it can support, but I can tell you that the mufflers are a straight through design with a couple of chambers the exhaust sound bleeds into.

Great info, no labyrith design that totally kills flow. Around 2" stock?

2.5"

LT's and a small can put me at 460rw through the factory cat back. (Very stingy Mustang dyno). It was 510 on a dyno jet.

I'm still running the factory h-pipe until next week and I'm over 600rwhp now.


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The stock cat back sounds like crap but actually flows very well. Like 2010reddevil said, it has a straight thru design. You will not see any performance benefit with an aftermarket cat back (besides weight reduction) until you get into the 600+ hp range.

Yea the things heavy. Especially the auto tranny exhaust

Thanks guys, great info! Sucks when it comes to weight... :( Any low weight quiet aftermarket systems? I hope the headers and de-cat will help to open up a bit of V8 music. :)

If being too loud is a concern then leave your stock cat back on. Do headers and your stock system will sound much better. The weight difference isn't enough to matter unless you are into some serious racing. There is a whole lot of people that would be better off taking some pounds off their own buttocks. Going from stock exhaust manifolds to headers is going to reduce lot's of weight.

I dont think the stock catback sounds too bad.
https://youtu.be/OH4RTu3AZ88

I didn't think so either. I've had a compliment or two on it. Most of the time people are just baffled that its stock, but 2" headers/catless seems to make it loud

That´s pretty loud! :) Thought it would be a lot more stealth on idle.

Its no stealth. It will tell you real quick what its all about...

Don't know if my ears are deceiving me, but it sounds like you have the same dreaded buzz/rattle that I do coming from your oem c/b.