Switch from 3" catback to 2.5", performance loss?
 

I installed a ALL PRO leaf pack and had to cut down my custom exhaust to make it fit. Went to midas and they rerouted my exhaust over the leaf spring. Upon driving fron the shop I noticed a decrease in power. I heard many times that a 3'' catback is too much for an N/A motor. Everyone suggested a 2.5". So when the opportunity arose I swiched. My exhaust note is considerably more quiet and the intake sound is lessened as well. I have a few pic for you guys to gander at. I'm thinking the mandral bends are a bit extreme. Whatcha think?

that exhaust is NOT mandrel bent..thats crush bent if the shop told you they do mandrel bends than they lied. sorry to burst the bubble.

Those bends are a little extreme but i doubt youll feel any real performance loss..its probably quieter because of that sharp bend above the axle. If they straighten it out it will be louder and will flow a little better.

not a fan of those angles

IMO, i feel 2.5 is still too much for a NA 3.4 motor, i feel 2.25 is the best way to go for optimal tq and flow. If you want something free flowing have that entire tail pipe cut off and have a turn down welded at the outlet of the muffler. Its going to sound like a muscle car.

2.25 inch past the cat, keep a muffler if you want, It'll clean it up, and then go for the 90* turn down. If you just want loud and ragged, do it without the muffler, but I would suggest keeping it in the formula.

i would start over and use 2.25'' pipes all the way back

thats what I meant, use 2.25 inch all the way from the collector past the cat, to the turndown, or to the muffler, and then the turn down, it'll have the big V-8 sounds, just not the loping idle.

sorry for the bad info. I said it was mandral bent not the shop. Now if I do a turn down after the muffler would I have any emmision inspection problems? I live in PHX, AZ.