Just installed the Mishimoto intake hoses today on my X. I couldn't find much about them when searching, so I thought I'd share my installation experience. I had heard that the HPS ones often need trimming. I didn't need to do so with the Mishimoto. Fitment is pretty good. Luckily the silicone is flexible with helps with wiggling into place.

The only hiccup was disconnecting the breather tube from the OEM hoses. They're a bit tricky to pull off. Removing the engine cover helps a lot with being able to maneuver the new hoses into place.

An added bonus (at least to me) is that the hoses are installed in the G on the opposite side that they were meant to on the 370z, so the Mishimoto logo gets flipped to the bottom side and isn't visible.

So far I can notice that it sounds a little throatier even with OEM filters. Next step for me is to drop in a high flow filter.

And now for pics:

Will this make any difference for the engines air intake?

No, very little if anything at all

i have the same ones but with k&n drop ins.i like it .better than wasting 400$ and getting no gain just some sound

I still don't know what to think other then ... if it has been dyno proven then it probably does give you gains... I thought of this, if the g37 sedan did not have the close gear transmission you probably would not notice a "big' difference of a gain compared to the v36 g35 sedan. Now if we're talking about 5-10 hp gain that an intake gives then it will not be noticed that easily.
just my thoughts but I do agree about it being overpriced.

One of the things that puzzles me is that the stock intakes are designed to take advantage of some ram-air effect and apparently gain like 4 or 6 (can't remember) more hp at speed. This is something that is apparently never taken into account when these cars are dyno'd; there's no replication of that ram-air effect. So essentially, any intake mod would have to at least add that HP back just to break even with the factory setup in real world driving performance. Paying a bunch of money for a throatier sound is one thing, but thinking you're gaining useable hp because somebody showed a few extra on the dyno may not actually be the best bang for your buck.

.02

these r smoother lines inside and its not bottle necked at all.its a improvment over stock especially with the k&n drop ins.hp i duno havent dynoed before and after but nice throttle response caus ei got the bully dog flash at the same time..so i really duno..100 pus k&n filter 175$ total.not bad...

dont forget! it looks nicer too!

Where is the decisive (not sales) proof of this? Do you actually think Nissan didn't very carefully consider what those wrinkles are doing for the airflow into our engines? There is a very good reason for them being there. Simply eliminating them may look better and seem more efficient, and may actually be for a limited rpm range, but in the big picture, there's a lot more going on than meets the eye. I won't botch it up trying to explain it, but I know it's real. Here's a link to some explanations of what I referring to:

http://hemrickperformance.com/induction.aspx

Or look up "Helmholtz Theory" pertaining to intake pressure waves or Philip H Smith's book "Scientific Design of Intake and Exhaust Systems", also a book by David Vizard on tuning intake manifolds.

I'll certainly concede you that.