Hey guys I know there are a million threads pertaining to test pipes and HFCs, but I am thinking of getting the invidia 50mm test pipes since they are actually the same outlet as the inlet of my oem hr y pipe, and thus wouldn't be like a bottleneck in exhaust flow. I am planning on running these with my oem hr y pipe, oem mid and muffler since they are the only test pipes with a matching diameter, and was just wondering if anyone has run this setup and what they're experience was? I remember reading somewhere that tony from motordyne said that in his testing 2" was optimum for test pipes, but I can't find the thread. Any thoughts? Other mods are k&n typhoon intake and motordyne 5/16 spacer and I plan on keeping the oem hr y on my de, as well as stock mid and muffler.

 

I found the thread I was talking about. Tony's chimes in on post #15 and gives some great info about his exhaust research.
https://my350z.com/forum/intake-exha...k-for-n-a.html