right now i got true 2 1.4 inch duals with 12 inch glassapcks and it sounds great with my mildly built 429, i was wonderin if i went to a single 2 inch with a factory muffler if it would give me more low end power

 

You're kidding right? Headers and dual 2 1/2 " all the way.

 

i was just curiousif the lots of backpressure woudl give me lots of off idle torque

 

A single 2" pipe is way to small. Most factory mufflers will restrict that engine. In a single, you would need a minimum 3" pipe, 3" exit Y-pipe, and a high flow muffler (due to the entire flow running through one). I would also suggest duals. I love 429s, Good Luck !!

------------------
2000 F-150 XL, RC, LB, 5.4L, 4R70W, 3.55LS,
Class III tow, Payload #3, & Convenience pkgs.,
4-wheel disc/ABS, Chestnut/Parchment 40/60,
Ford bedliner w/Paintsaver & gas/wheel/spare locks,
K&N F.I.P.K. w/Outwears pre-filter, Superchip,
Dynomax ultra-flow welded 3" cat-back w/ 3" Y-pipe,
Hellwig front & rear anti-sway bars, Rancho RS 9000s,
Mobil 1, K&N oil filter.