Biannual "Shaken" and Öhlins DFV Rebuild, Part 1

So the same Sunday I visited Nissan Prince to pick up some parts and replace the under bonnet insulation, afterwards I drove over to drop off my car with Ninomiya-san at his shop, BeAmbitious, in Yokohama near my house.  He is the only tuner/mechanic I've found who's been willing to do stuff most shops here in Japan won't.  For example, he had no problems (and even fixed an issue with the UK made brackets) installing the R35 brakes on my car (this was after Nissan Prince, Three-H, and even Mine's refused to install them), as well as the BNR34 diffuser install (again coming up with custom brackets).

This time, I asked him to take care of the bi-annual "shaken" - the road-worthiness "inspection" + plus tax payment required for all street legal cars in Japan and then, as Dino had agreed with me when he drove my car, to have the Öhlins DFV coil-overs rebuilt.

The shaken is something that HAS to be done, by law... unfortunately, the stringent rules means that, for any car that is moderately tuned, unless you leave your car with someone who knows a few tricks, or is required to be scrupulously honest and "by the book" (i.e. a dealership), your car will fail and be "mandated" to have expensive repairs done to make it "roadworthy" again.

Because Ninomiya-san has a long history of working on race and drift cars, he knows how to "massage" them to get them road legal.  For example, I'm pretty sure (and he agrees) the Tomei ExPreme titanium exhaust, as fitted on my car, is too loud to be road legal. And yet he apparently has a special exhaust insert which he uses to muffle the sound to legal levels. For cars that are lowered, there are ways from setting coil-overs to their highest setting, to over-inflating the tires, etc., to ensure the car has 9cm between its lowest point and the road. In any case, I can trust him to get the car to pass shaken with minimum hassle and fuss.

Also, I figured that, since the car would be with him, I would leave my old Nismo S-Tunes shocks with him (that I did not throw out), so he could put those on the car while he sent the Öhlins in to be rebuilt. Even though I don't drive my GT-R as much as I used to, as I have mentioned earlier I had recently begun noticing that the ride seemed a bit too stiff, with the coil overs not responding quickly enough.

As a refresher, here is the link to when I first had these Öhlins installed, as well as the propaganda from Öhlins  (Japan) as to what makes them better than the average aftermarket coilover. And here is what Öhlins (Sweden) says (they are now called their "Road & Track" model).  These following two diagrams, both taken from the English language website, demonstrate the difference:

 From the Öhlins website -  "Without DFV, the oil cannot flow through the piston quickly enough on the rebound stroke after a bump, so the tyre is not able to stay in contact with the road.

From the Öhlins website: "The DFV valve opens, letting the oil flow quicker though the piston on the rebound stroke after hitting a bump, enabling the tyre to stay in contact with the road."

When I first had the DFVs installed, even though they were pre-used the car would glide over small imperfections... and now, on the same settings, I seem to feel imperfections more, and at speed sometimes the rebound clearly doesn't react as quickly as it should, meaning the car bounces fairly hard.

Also, since the model I have was released, there have been some improvements Öhlins has made to the DFV model. Or rather, it appears that they now offer a "rubber bushing upper mount" model in addition to the standard "pillow ball upper mount" model which is what mine are.

So I left the car with Ninomiya-san asking him to take care of everything, the shaken as well as getting the Öhlins rebuilt with those rubber bushings...

The following Friday, Ninomiya-san called me, with the shaken already done!

Another customer car that was there... a race ready Chaser.

But when I went to pick up the car, he had some stories:

First, my car on the height adjustable Öhlins, set at their highest setting, only resulted in 8.5+cm off the ground.  So, he had to install the S-Tunes, which apparently cleared 9.0cm.

Second, my car was failed because the window film on the driver's side window was not clear enough(!) When I had the rear window and quarters tinted with dark film, I also had anti-UV film applied to the passenger and driver's side windows.  I did not recall what percentage of light they let in but compared to the rears the sides were relatively clear.  It turns out that the legal limit is 70%... that is 70% or more of the light has to be let through.  For some reason, the passenger side film DID let in exactly 70% and is thus legal... but the driver's side film let in only 69.5%!!!  Ninomiya-san thinks this is probably from all the usage (opening/closing) that the driver's side window which may have added minute scratches which then caused the difference.  The solution was to have the tint stripped off at the inspections center.  This however is a blessing in disguise as I will explain in an upcoming post.

Otherwise, he had no problems at the shaken center with the Tomei exhaust, or the Getrag conversion, or even the darkly tinted rear windows.

So, I paid the fees (about $1000 US for the shaken process), and drove home with the car temporarily on the S-Tunes... and it was weird... I'll blog about that in my next post.

More "Freshen Up" Parts and Some Trouble...

So as I hinted in an earlier post, the under hood insulation was not the first part I have recently purchased to freshen up the car.  A few months ago, after I got the car detailed at Rapt, I realized there were a few details that detracted from the overall "clean" car appearance.

These details are nothing large, but I guess the human eye picks up imperfections one may not be usually aware of.  For example:

So what exactly does this rubber trim do? Is it needed?

On this side too!

So normally something like this would not bother me (ok I'm lying, it bothers me to no end!). And I would try to figure out a way to repair it with the least amount of cost and effort (Superglue is a favorite...). But, the rubber had also hardened and so I wondered if it should be soft and pliable. As the second owner of this car, I know that this car was left outside most of its early life. And, despite many applications of products such as Aerospace 303 and other products to preserve and try to bring back the black, there was a permanent white-ish sheen of UV exposure that this cowl piece had.

When I inquired at Nissan Prince, I was told that I would have to replace the entire cowl in order to replace the rubber trim. So, I went ahead and ordered because it was a way to freshen up both aspects at the same time.

There was also this:

Windshield wiper arms showing wear and tear...

The yellow arrows point to areas where there are chips or wear on the wiper arms.  I had in fact previously used some semi-gloss black spray paint and resprayed the arms myself.  However I have done this twice already and it is likely that, since I don't do this painting in a controlled environment/have the paint baked on, the OEM part, designed for exposure to the elements, would likely last a lot longer.  Again, the car was left outside early on and likely, no one applied any sealant or wax to these arms (I am probably the only person who believes that ALL painted surfaces on a car need to be protected).

Anyway, since the wiper arms need to be removed in order to replace the cowl, it was only natural that, given the above thinking, I decided to go ahead and order some brand new wiper arms as well.

So it took a few weeks, but then I got the call so I went to Nissan Prince to pick up the parts:

After squeezing the cowl into the back seat (somewhat diagonally) I drove home and then life got so busy I wasn't able to work on replacing the parts...

Finally a few weeks ago (right before a business trip to Chicago) I decided to do the job, just in case the plane went down. Didn't want to die with unfinished business, right?

First, remove the wiper arms.  Begin by removing cap with small flat tip screwdriver (yellow arrow);
See how the faded paint detracts from the overall appearance? (red arrow)

Then use a proper socket wrench (12mm I think).

Next, remove this soft rubber trim piece by pulling the plastic "screws" out of the sockets

I'm now thinking, this is pretty easy...

For the original cowl piece, it's held on in 4 places with plastic clips, so just pull a bit hard (watching the outside edges where it tucks UNDER the windshield molding), to reveal:

The dust on the right, I expected. That rust, I did not!

Not just several years of accumulated dirt, but also splotches of rust! I was later told by the guys at Nissan Prince that this is very, very common ("there is always rust there"), so apparently a weak point in this car's design...

So you can see how the rust isn't just in one location...

Anyway, as I was trying not to faint from shock, instinct kicked in so I first reacted by doing what comes naturally, cleaning:

That dust is from all over Japan!

To:

Not finished but you get the idea...

Then after I calmed down, I realized I had several choices.  One, I could ignore the rust, put the new cowl piece on, not tell anyone, and hope that my refusal to drive this car in the rain would stop the rust from spreading; two, I could spray on some Rust-O-Leum and pray that indeed, it actually does "convert rust to metal"; three, I could take the car to a body shop and have them deal with it, or four, I could try to sandpaper/grind off the rust myself, and apply some primer and paint.

Normally, I would choose the third option - put all the old pieces back on, and then take the car to a body shop. But with funds tight and an upcoming "shaken" (bi-annual road inspection/tax) coming up, I decided the better thing to do would be to go to a body shop sometime in the future to take care of not only this, but some other issues I've spotted, all at once.  So for the time being, I would have to deal with just this section of rust - long time readers will know I've dealt with rust on the car before - I just would prefer to let a pro handle it, of course.

Also, the cowl itself now looked like this, so re-assembly with the old pieces was probably not the smart option anyway:

Uh, this is not going to go back on well...

So the night I got back from Chicago, I first taped up the surrounding areas like this:

And used #400 grit sand paper to begin manually removing paint and rust.  I soon discovered however that the rust wasn't as easy to remove as I thought, as well as under paint that didn't show bubbling.

You can also see the old under hood insulation which was
beginning to separate in some places - see how it looks puffy?

So I used my Dremel to quickly remove rust from all areas I could find, both visible and under the paint! Effective but not as "clean" as by hand. Oh well.

Luckily I had an unopened can of spray primer

Three thin coats of primer later (several hours to dry in between, of course)

After 3 coats, I debated spraying on some KR4 paint (I had a semi-used can left). However, I figured not only would the primer do the job adequately, and serve to show the body shop what I had done, I was also worried that the old KR4 paint might not spray well, and cause a mess. So I decided to stop painting and put on the new pieces (later at Nissan picking up the under bonnet insulation I asked them about this, and they told me primer alone was fine...)

New versus old

Checking out how soft and pliable the new rubber/plastic piece is:

Supple is the word!

And then I began to prep the new parts by spraying down with Aerospace 303 and letting it soak in:

The underside, which won't see daylight again until it's removed.

And the topside, which will!

Installation was the reverse of taking the part off, being careful to make sure the plastic clips went in on both sides, and that the edges were tucked in under the windshield molding.

I found out that the rubber trim piece is actually about 1.5cm too long on each side - cutting required.

I then attached the rubber piece to the front of the cowl, which helps to secure it better (as otherwise only 4 plastic clips are holding it on).

And then I just swapped out the old wipers for new, transferring the blades over.

If you are curious you can make out the parts numbers...(28886-15U00 and 28881-15U00)

Then I just bolted the wipers back on, put on the plastic caps which cover the bolts, and I was done!

(photo)

Speaking of parts numbers, here are the others for completeness sake:

So what's next? Luckily, there are no other places with that level of rust.  However Japan being a humid place, plus because I like to wash the car, I guess I will have to be careful going forward.  That being said, there is some bodywork I'm still thinking about, so maybe at that time I can get this under cowl area redone professionally.

In any case, the car looks like this now:

Ahhh Yeah! Perfect!

I hope this was an interesting and useful post! Sorry about the length...