NSX-R Chassis Bars Installation
Before starting the installation, I researched installation techniques and talked to a couple experienced folks on the best ways to go about it. For the most part, everyone agreed that it could be done without removing the bumper, but on my 2002, it just didn't seem that way.
The lower chassis bar is a simple and easy installation, so I decided to tackle the upper bar first. That way, if I didn't get the front bar installed, I wouldn't be driving around with only the lower chassis bar installed.
I started by installing it from underneath. It appeared to me that it would be impossible to remove the front radiator duct because of the way it was wrapped around the air conditioning tubing. Second, I tried leaning the radiator back by removing the top radiator supports. Again, could not remove the front radiator duct. So I decided to go ahead and remove the bumper. That way I would have much better access to the tie-down brackets and work with the fitment issue that I was expecting with the upper chassis bar brackets.
I started by unplugging the horn, the ambient sensor, and the power connector to the windshield washer fluid motor. (I could not grab the windshield washer fluid hose, so I decided to remove it once I got the bumper off.) I remove most of the screws and pushpins that held in the fender liners to gain access to the bolt (bottom hole) and two nuts that held the bumper to the fender.
(Click on photos to enlarge)
Then I removed the two access covers on the 2002 OEM bumper. This allowed access to the two of the six bolts holding the bumper on to the front frame plates. Once I removed all six bolts, the bumper was off and I could disconnect the tubing from the windshield washer fluid motor.
Next, I removed the pushpins from the top of the radiator ducting and removed the duct. Notice the outline imprinted on the duct to indicate where to cut for the installation of the upper chassis bar.
I removed the tie-down brackets and started checking the fitment of the front chassis bar. There are several other threads which address the issue, but, since I wanted to keep both of my tie-down brackets, I went with the idea posted by MJK (see his post here). I used my grinder to remove about 20mm off the trailing edge of the left tie-down bracket.
This photo illustrates the spacers (two washers) used to offset the upper chassis bracket from the right side tie-down bracket. Notice that the chassis bracket is placed on top of the tie-down bracket.
This is a view of the left side bracket. I used spacers (three washers) here also to allow for the offset. Notice the chassis bracket is underneath the tie-down bracket.
The three washers under the left side tie-down bracket.
I had one more fitment issue. I needed grind part of the tie-down bolt washer to allow clearance for the bar.
And the bar is installed.
Photo of the radiator duct after cutting along the factory outline.
And the fit is perfect.
The bumper went back on quite easily. It's best to have one other person to help because it is possible to scratch the paint with the lower part of the bumper against the lower-front corner of the fender. I didn't scratch mine... but I came close. So, I got help.
Installing the lower chassis bar is simple. Remove the two front bolts holding up the spare tire/battery tray, loosen the rear bolts, and allow the tray to drop down slightly. Remove the correct bolts and replace with the lower chassis bar installed. Be sure to TORQUE the two bolts (with a torque wrench) to 69 ft/lbs.Post Installation Test Drive:
I wasn't sure I noticed a difference... maybe just a slight improvement. Others have stated that they could easily notice the improvement. It may be harder for me to notice a difference because I still have the stock suspension.