hi guys i have a 08 4.7l and i purchased the y pipe 2.5 in 3 o and i want to buy a magnaflow si/so. muffler shop said i will lose torque and hp if he installs the y pipe and i only want single pipe not dual. is this true. what is my best option i would appreciate your guys help.

 

Dont you have a factory y pipe now?

 

yes its in the box i havent installed yet

 

im slow with computers sorry for delay

 

im only buying muffler from the shop and getting the y pipe installed at the same time but muffler guy said that he has a magnaflow clone in ss. everything comes out to 160.00

 

yes i do have the factory y pipe but aint it more narrow than the magnaflow one

 

yes i do have the factory ypipe on

 

Yeah thats what i meant, you already have a factory y pipe. So having one less restrictive and more free flowing is better IMO

 

he also said at a complete stop thats were it loses torque at take of and then in highway it would yes be better is it true.

 

i went and got muffler installed si/so left factory exhaust.i havent installed ypipe yet just waiting advise from this great forum. but it feels like its drowning like loss of punch, power. But sounds very good .