I'm almost ready to put better exhaust on my 99 Expy and was curious if running true dual exhaust with glasspacks would be ok? I hear that on 5.4's if they breathe too easy they actually lose low end torque. I'm looking for some rumble and more low end torque. Any input would be greatly appreciated!

 

Don't waste the money on glasspacks. I did the same thing on my 01 super crew and it was not good.Sound was unbalanced the low end power lost was unbelieveable.Man a yugo could beat me off the line.So I finally had a custom y-pipe made then ran 3" pipe with a single chamber IMCO and love it. the power is better than stock and the sound is great.