A Tuner Guide QR25DE - interesting article.

[Nlghtmare]

http://www.modified.com/tech/0....html

I just came across the article. Although it is almost a year old, it is rather interesting and explains a lot about the QR25DE. It's always fun to read from another perspective. Just get to the end though.. I knew the exhaust systems on Nissans were restrictive.

[QR25DE]

Yeah read that a long time ago. Yeah the stock exhaust manifold is VERY restrictive. Also after the first cat there is a part where the exhaust flattens out. I hope when people buy the Cat-Backs that they realize they need to get custom piping made there from the header to the cat-back exhaust or else it's just a whole waste.

[toxik]

qr25de is the first to reply.... oh the irony

[PHENOMenalVinyl]

qr25de is the first to reply.... oh the irony

[XXplosive990]

I hope when people buy the Cat-Backs that they realize they need to get custom piping made there from the header to the cat-back exhaust or else it's just a whole waste.

this part confused me...lol

[el_blacky06]

hes talking about the exhaust system midway thru it, theres one part of the stock exhaust that goes flat which restricts the air flow dramatically

[QR25DE]

hes talking about the exhaust system midway thru it, theres one part of the stock exhaust that goes flat which restricts the air flow dramatically

[mcheddadi]

its for low end torque that part. sacrifies high end but more than makes up for it in the lowend, at least on the VQ thats what it does lol

[migs7585]

Also after the first cat there is a part where the exhaust flattens out. I hope when people buy the Cat-Backs that they realize they need to get custom piping made there from the header to the cat-back exhaust or else it's just a whole waste. [/QUOTE]

So just buying a whole cat-back doesn't fix this??

[SuIiCiDaL]

also seeing this have you guy seen the headers on the 2.5 they are hard plastic i know b/c i have one

[QR25DE]

Also after the first cat there is a part where the exhaust flattens out. I hope when people buy the Cat-Backs that they realize they need to get custom piping made there from the header to the cat-back exhaust or else it's just a whole waste.

So just buying a whole cat-back doesn't fix this?? [/QUOTE]

Nope it doesnt. The cat back bolts up after the 2nd cat... not the one that comes off your header. Correct me if I'm wrong but on a few exhaust systems thats not what i have seen. It bolts up after the 2nd o2 sensor. (Notice how the cat backs you buy do not have a spot for the o2 sensor).... just an FYI.

And about the headers being hard plastic? WTF ARE YOU SMOKING? They would melt. Obviously you are talking about the intake manifold? Yeah that's plastic... ???

Wha?

[migs7585]

Ok....So basically I'd need sumtin custom made after the second cat? I'm planning on getting the Stillen headers and a full cat back but I really wana open her up as much as I can.

[QR25DE]

Ok....So basically I'd need sumtin custom made after the second cat? I'm planning on getting the Stillen headers and a full cat back but I really wana open her up as much as I can.

Header -> Custom Pipe with secondary o2 sensor bung welded in -> Cat Back.

[migs7585]

nice....thats for the info....how much extra hp is all that supposed to give? plus an intake

[QR25DE]

Probably no more than 15-20. You'd feel the difference for sure.