DIY ZSpeed NISMO 370Z Aluminum Under Pan Diffuser

wind.zero

I ordered this from Joe at ZSpeed as soon as it was available. I also have the GTM SC Stage 1 installed which caused some installation hassles. In other words, it is not a perfect fit because of the IC piping and the oil filter relocation kit, but it is pretty close. I appreciate the help and excellent customer service from ZSpeed.

First, the product is of exceptional quality and is shipped in a quick, safe, and professionally manner. I literally had the items in hand 3 days after ordering them over a weekend.

Second, I had some install and fitment issues due to the GTM SC kit. These issues DO NOT apply to a NA NISMO. Please don’t let my issues hinder your order of the kit.

The GTM SC kit uses the vacant space on each side of the bumper which makes fitment challenging. In fact, fitting the OEM plastic piece is really tight. The IC piping/air filters occupy the passenger side, and the oil filter relocation kit, oil filter, and oil cooler are stuffed into the driver side. Thus, installing something less pliable like aluminum is a little difficult. Joe has some variance in the mounting points but not enough to perfectly cohabitate with the SC pieces.

The install is as simple as removing the obnoxiously expensive (~$930 USD) OEM plastic piece and replacing it with the three pieces from ZSpeed. The only real tip I can give is to install the side pieces first, then align and install the middle piece. Also, since I am SC’ed the oil change access panel gives a great view of a sandwich plate and oil lines, but I knew this from the start. However, oil changes can be performed by just removing the center piece rather than all of the pieces so it is still simpler.

I am tired of seeing this:


So the primary reason for ordering the ZSpeed kit was for the vent to pull in air directly to the oil pan. Plus, I think it looks better than plastic and provides a greater degree of protection from road debris. I know that I could have cut a hole in the OEM plastic piece, but that thing is expensive and I was not motivated to cut it. I will keep it to return the car to stock if that day ever comes.

This is the $930 OEM plastic under tray


Packaged ZSpeed Aluminum Under Pan Diffuser


The side pieces


The center piece


The problem areas because of the GTM SC kit


The biggest problem is the IC piping on the passenger side. This contact causes a cold start vibration which goes away after reaching operating temperature. I am going to try and isolate the vibration with some cut radiator hose between the IC piping and the diffuser.


I used some high temperature resistant loom for now, but still have the vibration.


One mount point had to be zip tied on each side piece due to tight fitment with SC parts. This shows the driver side. It is the same location on the passenger side. It is the deepest hole so the wheel/tire hides the view of the zip tie area. On the driver side, the bolt would hit the oil lines, on the passenger side, they just do not line up due to the IC piping skewing the ZSpeed part.


Also on the center piece, these holes do not align. With all of the other mounts tightened down securely, everything still appears to be very secure. There are still 6 mounting points in the front and 4 along the back. I do not think missing these 2 is the end of the world. Again, this alignment issue is due to the GTM SC kit and not ZSpeed.


This shot shows the air vent and flow to my GReddy oil pan.


Driving Impressions:
It has only been on for four days. I have a cold start vibration which I believe is from the IC piping contact. It goes away after driving about 5-10 minutes. I hope to cushion or isolate the vibration with some split radiator hose where the metal on metal contact is occurring.

The highest oil temperatures I have seen so far have been in the 220 range. However, it has only been in the low 80’s and I have not really gotten on the boost yet. So far so good.

I encourage anyone with a NA NISMO to get this kit. I think it is well worth the price of admission. If you are FI (SC or TT), you might give it some thought.

Thanks Joe @ ZSpeed.

Oil cooling efforts so far ….

1. GTM 25R Oil Cooler
2. GReddy Turbo Oil Pan
3. Venter Fender Lining
4. ZSpeed vented Under Pan Diffuser

Coming soon: SPAL pusher fan on the 25R Oil Cooler.