These mufflers are built with valves inside that do restrict the exhaust but how much pressure is supposed to be at the tailpipe when car is in neutral?
i can hold my hand over the tailpipe and no change in engine sound is that normal?
other cars i drive have a lot more pressure at the tailpipe but i cant feel the pressure when im reving it up i dont have another person to rev it up.

 

Are you plugging both tips?

 

They said exhaust only comes out of one tip until you accelerate.
then a spring loaded valve opens allowing pressure from both tips out.

 

It does and I actually have been able to tell a big difference in Glee's (the Gle) performance when I put the factory calsonic muffler from my 2k 5 speed on it. I had done some preventative maintence to Glee by removing the precast and because it was cheaper than replacements I went ahead and installed the ebay headers and y pipe. It was already mufflerless due to my dad having the awesome stock muffler replaced because the b pipe rusted instead of welding a new b pipe to it. He opted for some cheap job don't know the brand and whatever fiberglass looking packing that was in it was clogging the holes due to the inerds already rotting out. I also had a good test pipe laying around new never installed for my old rx7 I haven't gotten around to fixing. So I ran headers, y pipe, stock resonator with the pinch point cut out, replaced pinch point with a round piece, and the rest ran to where it was supposed to meet my muffler. No cats. Car was peppy which even though I wasn't trying for that was nice. But I noticed the low end torque loss everyone mentioned for sure. Tried 6 differents types of mufflers for sound and back pressure none really helped the low end. Until I got the 2k 5 speed. Borrowed its muffler because it's a project car now and doesn't need to be quiet. Big difference. On cold starts you can see the one pipe not breathing and feel the low torque again. Buddy said he saw it start breathing when I revved it one day but I've yet to take time to record or have some else Rev but I'm pretty sure it's good. I'll also add. The vq30dek straight piped all the way to the resonator and terminated at the stock muffler sounds better than any other muffler or exhaust setup I've seen and heard on these cars. It has a tone at idle and a great sound when on it. But is quiet and drivable. No drone at all on my setup.