Custom intake with Z1 Motorsports post-MAF silicone intakes and K&N drop-in filters

[Athlon]

Hey, guys. I decided to try and go ahead with a simple modification of the stock intake. I had sent back the Top Speed intake. I purchased the Z1 silicone Post-MAF intake hoses for the 370z/G37. It fits the FX35 with some slight modification. The hoses have aluminum tubes that connect to the factory lines. These tubes can be removed. On the drivers side, the aluminum tube was removed and connects to the existing plastic factory line. On the passenger side, I had to keep the aluminum tube and cut a piece of the factory tube to create a seal where the two connections met and use the metal factory clip. This is because the factory line on the passenger side was bigger than the one on the driver side. The aluminum tube on the post-maf hose actually fits inside factory line on the passenger side, but the part of the actual post-maf hose overlying the aluminum tube is the same diameter the factory line (See pic #2 and pic #5). I recommend using Marvel mystery oil when trying to fit the intake tubes over the throttle bodies and the stock intake boxes. I didn't and this thing was a huge pain to put on without it. Took me like an hour of forcing them on. lol The K&N drop-ins were too easy to replace.
As for results? The intake seems a tad bit quieter than stock on startup and at low speeds; there's less of that classic "growl" to my surprise as I thought it would be a bit more aggressive all throughout. However, the roar is better, louder, and more refined in the mid-range to high-range, especially at WOT. The FX throttle response feels a bit more responsive and seems to accelerate quicker when passing at highway speeds. Without further adieu, here are the pics and the link to the Z1 Motorsports website.

http://www.z1motorsports.com/g37_370z/product_info.php?cPath=597_603&products_id=5292

 

[cheste1]

Nicely done!

 

[PEEJ]

Good job! Now all you need to do is remove both air boxes and grind off the internal baffling. Boom!

 

[Themechanic]

Hmmm interesting. Sometimes i wonder why automakers design intake tubing with all those ribs in them if its only gona restrict airflow. Very nice work!

 

[PEEJ]

I agree. Don't restrict power when there are better ways to dampen noise.

 

[Athlon]

Thanks, guys! I'm glad it worked out. A nice and inexpensive mod in the grand scheme of things.

 

[Athlon]

PEEJ, I looked into your suggestion. The stock air boxes are pretty well designed and don't seem to have much baffling in them. There's a U-shaped scoop that directs air from behind the grill to the drop-in filter. Don't really know how one can improve any further on the stock intake, but feel free to correct me if I'm wrong.

 

[shadow191]

There aren't really any gains on the intake side. OEM intakes are pretty well designed as is and all of the aftermarket filters make no power or lose power.

Sort of like the Z tube on the first gen; in theory you'd gain power by removing the stock resonator which looked restrictive and having smoother piping on there. But this was never proven in practice and they never really had repeatable gains from the Z tube alone. Some people even had slower times in the 1/4 with a Z tube when compared to the OEM intake (not much slower, but it was measurably slower and repeatable). On VQ's including the HR, the intakes seem pretty well designed and anything aftermarket is just for looks and sound.

Having said that, I like that you're trying something new and actually took the OEM box apart to look at it, plus it looks good.

 

[jbaker1121]

add some heat shields or ducting to keep the air going in cold if you must keep an aftemarket intake.

 

[wyatth]

This is a popular mod for G/Z owners but I can't find much on the FX/QX. I imagine it's nearly the same to install on my my 3.7 as it was for you. Would you do it again?

 

[Athlon]

This is a popular mod for G/Z owners but I can't find much on the FX/QX. I imagine it's nearly the same to install on my my 3.7 as it was for you. Would you do it again?

I definitely would. However, I would use some lubricating oil to get the hoses on. That was the longest part of the install. It didn't dawn no me to use a lubricating oil/grease beforehand. I wrestled with getting them on for like half an hour. lol

 

[trhyne04]

Did the top speed set up not work?

 

[Athlon]

Did the top speed set up not work?

Definitely sorry for the late reply. From what I read, it wouldn't be worth it on the 3.5HR motor. I ended up going with Stillen Gen 3 intakes which really made a noticeable difference.

 

[Who_Ryder1]

Hows the mod going? I got the HPS ones and i need to modify the passenger side one because the hose nipple thing is too small for the plastic plastic factory thing... (not sure that that name is)

 

[LA_DRIVER]

To everyone saying the stock air boxes are fine and cold air intakes aren't worth it I beg to differ. You can literally hear our car struggling for air when you take off at full throttle. So today, I put the Z1 CAI that is now CARB legal on my 2015 QX70. Had to cut holes in the radiator support like others have done here (thanks for the photos!), but honestly it was super easy with a hole cutting drill attachment I got off Amazon. The silicone elbow tubes are definitely crucial as it's still a tight fight on the driver's side.

I could tell immediately that it had more power and better throttle response throughout the lower gears. I've yet to take it on the highway, but our car never really suffered there in my opinion. Z1 claims that these can add btw 15-21hp on a stock 370z (I trust them). So far I'd say that feels about right. It's clearly an improvement. Also it doesn't have a loud "whooshing" sound either, which I'm ok with. If you are after a certain sound then these filters don't do that. They offer racing velocity stack filters for an extra $200 those look like traditional CAI filters.

I also did a throttle body idle relearn using the Z1 scanner and it dropped the RPM's down a bit so it seems to me that more air is flowing in now than before. I also have ISR high flow cats and an Invidia catback, which combined with this intake really opens the car up from end to end. Sounds great too.

UPDATE: I ended up upgrading to the larger velocity stack "race" filters. Definitely a slight improvement. I suggest just getting these instead of the smaller regular ones that were meant to fit the cramp space of a 370z.