I'm curious why as I'm planning my dual setup (5.4 '03 screw) with 14" magnapacks. I see everyone says you lose a significant amount of TQ going with the 2.5" setup. For those that did choose that route, why? Is the 2.5" setup significantly louder? Deeper? I won't be towing anything with my Screw other than an occassional small open trailer with 3 dirtbikes (most of the time would only have 2 in the bed only). I do however plan to lift in the future.

Thanks!

 

2.5" sounds a pinch clearer and better under WOT, performs better on WOT too. If you dont tow alot, or have ah huge lifted truck, 2.5" is fine.

 

If I had to go back and choose between the two, I would probably go with 2.5" pipes.

 

Thanks guys for always replying to my threads. Great advice as always. Do you know if there have been any real #'s shown of how much TQ is really lost? Is it significant #'s wise or more the but dyno feel?

I'm not sure my lift plans yet. It will definitely be 6" and may somday add another 3" BL. Even at 6 or 9 inches of list, wouldn't proper gearing and a tune take care of any "loss" in performance? Not trying to convince myself that 2.5 is better...just trying to understand the differences.

Thanks!

 

If you plan to add custom tuning, gearing, an intake, and a straight through muffler, those will all have a more significant affect on your torque than a 1/4" difference in pipe size. IMO I would go with whatever is cheaper. But if you plan to someday get forced induction, do 2.5".

 

I would do 2.5". I have 2.5" all the way with an X and it sounds good at all throttle ranges. My 2 flows will be gone tomorrow for 2 magnaflows and it should be even better haha