jhatch471

So I'm about to make my first power modifications to the Z and am starting to question where I should place the HFC/s. My "Stage 1" upgrade will consist of the K&N drop in filters and a one of the following combinations:

Option 1) Berk HFCs & XYZ Motordyne Y-Pipe w/Straight Pipe

OR

Option 2) Berk Test Pipes & XYZ Motordyne Y-Pipe w/HFC

I plan to get the Osiris Reflash/Tuning software as my "Stage 2" upgrade so I'm not worried about the CEL/SES light in the near future. Could also do the anti-fouler method.

The price difference is within $20 (for option 2) but I'm not worried about this either.

Here are my thoughts:

Option 1) This gives 2 places for the exhaust flow to be restricted, at the HFCs and the joint of the Y-Pipe. Could be good pressure, it may be too much restriction.

Option 2) This gives 1 place for the exhaust flow to be restricted, at the joint of the Y-pipe but its also the location of the HFC. All restriction in 1 place, good or bad???

Your opinions on its/their optimal placement?? I don't see an obvious winner yet but tend to lean towards option 2.

vnarang

iTrader: (7)

Uhh, can you have HFCs and Test Pipes on a car?

Correct me if I'm wrong, I don't know sh*t, but isn't it, Headers>Cats>Exhaust Components (Midpipe, Muffler, etc.)?

chrisaray

iTrader: (3)

I would go with your option "1".

It seems to me that it would be better to have each half of the exhaust going through it's own HFC rather than trying to flow all of the exhaust through one HFC of roughly the same size.

chrisaray

iTrader: (3)

The Motordyne Y-Pipe gives you the option of running a single HFC, or a "test pipe" after the Y-Pipe.

Chef-J

iTrader: (58)

...ahh...wut? ok.........................

Let's use right words. I'm not good at english but i think i know what is straight pipe or resonator. lol

Here XYZ pipe you can choose

-resonator
-straight pipe
-Catalytic Converter

Edit: from your choice, both of them are good setup, nothing to worry about air flow.

jhatch471

^^updated my post. I come from the Evo world and have always just used the "test pipe" as the straight pipe instead of a cat.

Agreed that this seems weird, just looking for opinions on placement.

Chef-J

iTrader: (58)

^
but Wut exhaust tho?

singh

iTrader: (2)

I am assuming he is going to use the stock Nismo muffler that comes with his Nismo edition Z.

Go with option one. You won't have to worry about the stupid CEL, and I believe it is to your advantage to place the cats at the beginning of the exhaust flow. Nissan put placed their cats in that particular location for a reason. I trust their engineering over some guy on the internet.

kramerbuccs24

Yes, they did have a reason, and their reason was emissions

jhatch471

Yes, I will be staying with the Nismo Edition exhaust that comes with the car for now.

I appreciate everyone's insight so far!

singh

iTrader: (2)

Maybe you should re-read my post captain obvious.

Out of all the places Nissan could have put the catalytic converter, why would they place it directly after the exhaust manifold? Couldn't they have just placed it somewhere down the exhaust path, like say right before the muffler?

Justin@IOS

iTrader: (3)

I believe they put the cats as close to the combustion chamber as possible to help them heat up quicker to reduce cold start emissions.

jhatch471

I think it's a valid point to make that there must be some reason Nissan put them there. Remember some of the Camaro's that had 1 catylitic converter after their y-pipe? There were a few years where they did 2 cats right after the headers. I don't know the reasons why they choose to put them where the did, but I'm sure there was a reason too.

Not sure if the reason was for higher maintenance costs when it all starts to wear out or if it was for better exhaust flow.

I will definitely take this into consideration when I make my final decision.

kramerbuccs24

Why so hostile??? The smiley was there for a reason.

I didn't mean that in the obvious sense that the cats are there for emissions, I meant along the lines of what Justin was saying.