# Megan Racing Install **URL:** \ **Category:** Canada Nissan Automotive\ **Created:** [April 15, 2007, 6:30pm UTC](https://forums.speedlife.net/t/megan-racing-install/133325 "2007-04-15T18:30:28Z")\ **Posts on this page:** 1\ **Showing post:** 9
**Author:** ![jschrauwen](https://avatars.discourse-cdn.com/v4/letter/j/a88e4f/32.png) [@jschrauwen](https://forums.speedlife.net/u/jschrauwen)\ **Post date:** [April 16, 2007, 7:07pm UTC](https://forums.speedlife.net/t/megan-racing-install/133325/9 "2007-04-16T19:07:05Z")
> [@somthin for the nissan guys](https://forums.speedlife.net/t/somthin-for-the-nissan-guys/1414/8): > > the X-pipe does help with some scavanging in a NA car, but im pretty sure on a turbo car, the energy from the individual exhaust pulses is absorbed by the turbine in the form of heat and mechanical energy. on a turbo car, the goal is to have as little back pressure as possible, the ideal exhaust would be none at all after the turbo. if there is no back pressure, the turbo spools faster and thaz how you get your low end torque. what you said about smaller diameter exhausts giving more torque is correct, but only on NA cars. that is why im going with a 2.25" on my NA SR build. > considering it is a twin turbo rather then a big single turbo, i am pretty sure you’ll be fine with 2.5" and you cant beat stainless steel! that exhaust is beautiful. it must sound awesome! Ahhh, OK, well that makes sense. And thanks for the props too. Maybe that’s why the turbos spool up quicker now. That and the AIV delete has added a bit to it’s character. The exhaust note is not harsh at normal throttle speeds but does have a nice growl we you get onto it. Highway speed note is good once above 110kph. > [@TIF's wtf!](https://forums.speedlife.net/t/tifs-wtf/1380/3): > > ^+1 on the xpipe… > But since your TT a 2.5" would be min dia to use… 3" would be optimal. > R:drivin 3"?, Hmmm, I didn’t know that. The oem was tiny - 2 1/16" OD. My research on other Z boards didn’t emphasize the need to go any further than 2.5". I think the split downpipe has some extra benefits too that the oem system didn’t have. There weren’t any catback systems within my price range that eliminated the H or X pipe config. Now, to make sure I can pass the next enissions test. :rolleyes: --- _[View the full topic](https://forums.speedlife.net/t/megan-racing-install/133325)._