Saturday, August 31, 2013


Over a year ago, when I embarked on the sound deadening project I had bought several spray cans of this:

Looking at reviews online in Japan, this product (the "Beat-Sonic Noise Reducer") was generally acknowledged as the best, not only in sound dampening ability, but also as a general undercoating (to prevent rust) in cars.

Luckily, as they don’t use salt on the roads in the winter, and also because I frequently wash my car, there are very, very few spots of rust on my car.  The few spots that I have spotted were surface rust on the car when I first bought it (mostly easily removed), and I haven’t seen any new spots since.  So really, there really is no need to apply an undercoating, so long as the car is in Japan and relatively well maintained.

Here is the worst of the rust.
I was hesitant to spray this on for a few reasons – one obviously is weight, but the other was, would this material be removable in case there was a spot of rust that got out of hand and that panel had to be repaired?  Again, is it really necessary for me to do so?  Sacrilege to unnecessarily paint my car??

In any case, I thought I reached a happy compromise by deciding that I was going to spray ONLY on the inside of the fenderwells, behind the wheels, where I suspect most of the road noise was getting through (because the floor had been lined with the sound deadening material already, on the inside) AND because I planned to spray the stuff ONLY on the plastic fender liners.

So, I jacked up the car, took the wheels off, then liberally sprayed on some Simple Green to break down any dirt there.

And yes, I also took the opportunity to clean the wheels, especially on the insides where there was some brake dust.
Hard to clean as those calipers leave only a few millimeters of space

Oh, and yes, what a great opportunity to clean the R35 brembo calipers!
This dirt had been bothering me for a long , long time...

I then used my trusty Vapamore steam machine to REALLY get things clean.


After (and after I started wrapping with newspaper):

I then covered up all the important components with newspaper, and began to spray on the undercoating.  But then realized that, I might as well go for the metal too (which, I believe, already has a CLEAR looking (but now yellowish) factory undercoat in some places)

So here is how it looked after spraying on the undercoating.  In addition to rust protection and sound deadening, I realized then of another advantage – of making the inside of the wheelwells look dark, thus enhancing how the wheels look.

And the result? Nice and CLEAN and  Oh, and also as the pitted plastic liners are now covered with the deadening, hopefully they will be easy to keep clean now.

As to whether the coating had an effect on road noise, in my judgment, "yes" but only slightly. Then again with the Tomei Expreme exhaust uncorked, it was a bit hard to "hear" the difference over the exhaust note, but during the Izu Skyline run, it just seemed that under some circumstances, the car DID seem to have a bit less road noise...

The background is all black....

1 comment:

Adam said...

Ah what a coincidence. Just did the fender wells on the Silvia a few weeks back. A well deserved service on an older car.