FM40's weld-in vs Catback

[LouisianaZJ]

04 GT, w/an o/r H (MAC) otherwise stock.
How much difference am I actiually going to see with the weld in 40's vs' the mandrel FM american thunder catback?

 

[LouisianaZJ]

btw, I was thinking about using the savings in cost to do the C/L plenum ($180) and a 70mm TB (not sure which brand)

 

[JBushman73]

I basically posted the same question earlier. I'm anxious to find out also since I have an 04 with Mac Offroad and FM 40's.

 

[03redfiregt]

personally the differnence in horsepower your going to see between weld in mufflers and a full catback is very slight. your would'nt notice. But thats my 2c

 

[twogts4us]

Agreed - the difference will likely not be enough to notice, maybe 5 HP. BUT, if you plan to get headers, you'll want the full catback.
And some unwanted advice on the TB...buy what everyone tests with - the Accufab.

 

[BNH4.6]

The only thing you will notice is a slightly deeper/ louder sound. SLIGHTLY!! Power wise maybe 2-3 rwhp maybe.

 

[flashstang04]

I opted for the weld ins with a high flow cat pipe, and honestly, I can't tell a difference (power wise) between mine and a friends with the cat-back. An O\R pipe will be a little louder, but not much at all.