Tuesday, April 27, 2010

Track Day at Fuji Speedway with SSCT/ Ohlins DFV Report, Part 2

This past Sunday, was joined by my friends Miguel and Alex at the Skyline Sports Club Tokyo (“SSCT”) trackday at Fuji Speedway, on the Racing Course. Miguel in his RX-7, and Alex in his R32 GT-R.

Weather was absolutely gorgeous! Quite a welcome reprieve from the usual rainy weather we’ve been having lately. There were about 50 cars (mostly RB26 GT-Rs!) in total, making for a very crowded track at times!

We checked in at 0830, then began to get our cars ready for the one hour run beginning at 1100. For Alex, we decided to try something different – so we fitted some BF Goodrich slicks on 17 inch black rims (remember my project wheels – that’s who I sold them too…) to see if it would make a difference. Although last time, Alex drove the racing course in an amazing 2’13, not bad at all for a first timer!

During the prep, I got a call from my friend Sumi-san, who offered to stop by and “study” – what exactly, I had no idea.

Here is his blog – he’s a Nissan fan and S15 driver who really knows his stuff!

He surprised us by bringing along a datalogger (which he put in Miguel’s FD – fair to compare after all as it’s FR just like his Silvia). He also agreed to take photos with my Nikon (thank you again, Sumi-san! Arigato!) So all photos here are his work!

Once we got the prep work finished (just barely in time), we lined up and entered the pit lane.



Here we are, lined up ready to go!

And we're off!!

I decided to run the DFVs on the medium (10 of 20 clicks – the “windy road”) setting, hoping that this would work well with the 18 inch S-tires on the RE30s. On the drive to Fuji Speedway on the same S-tires, the ride had been fairly stiff, so given Fuji’s high speeds, I though the setting might work.

Once we started the run, the car was much better controlled than before on the S-tunes, but I could tell that the springs were a bit soft and the compression needed to be upped. However, the change in the car’s general behavior was dramatic. For one, I could no longer do the “left foot brake tap” at Netz corner (causing the car’s nose to dive to the front, shifting the weight of the car on the front steering wheels very quickly), forcing me to try a quick trail-braking and downshifting in midcorner instead. But, on the long smooth sweepers, the car was amazingly stable, and I could feel what the car was doing so much better than before. It’s not as direct/hard as a race car, of course, but this time around I could really sense how the S-tires were heating up and getting loose, progressively, lap after lap. With the S-tunes, I’d really only notice the tires getting too heated up and inflated only when I started losing the back end in sharper corners. In retrospect, that’s how vague the feedback was I guess.

In terms of setting my best time ever at Fuji, unfortunately there was probably too much traffic, (50 cars) and I don't think I ever had one lap where I could go full out. Same with Miguel and Alex. So, I pitted twice – once because I had told the guys I would do so, the second time to adjust the DFVs and reduce air pressure in the tires. I reset the DFVs for a much harder setting, 2 clicks from max up front, and 3 clicks from max in the rear. In retrospect, maybe no clicks or 1 click back might have been ideal.

Back on the track, the car immediately felt even more stable and more communicative. However, now I was dealing with another problem – the brakes. The PFCs rotors are very good, and the pads too, but for some reason felt like they had begun to fade halfway through the session - usually they last me until the last 5 minutes. I later discovered that the air cooling hose had been torn in two…again! So it wasn't the rotors, it was most likely the fluid! I need to figure something out here. So my driving for the rest of the session was tempered, in that I was not about to exceed the remaining capacity of the brakes. Credit to PFC, the brakes FELT mushy, not as immediate as before, but still worked to haul me down from 260kph plus!

No way I am passing the Jun car - he's pitting.

It can be lonely on the straight...

In the end, Miguel had a 2'03, I did a 2'04, and Alex came in with a best of 2'07. Amazing for Alex, as he's only been on Fuji twice! Miguel was the only FD, but Alex was the 4th fastest R32 (out of dozen or so), and I was the second fastest R33 (out of 5 - the 700hp Jun Lemon thing was faster than me by 3 seconds...)

Afterwards – Miguel reported something wrong with his LSD, and Alex claimed he needed new brakes. Apparently he cooked his brakes and ran off course a few times. Can’t wait for THAT video to make the YouTube rounds!

On the way home – I had forgotten to set the DFVs on their “windy” setting – which made for a really punishing ride, even on Japan’s super smooth expressways. Amazing what 8 clicks does!

So in summary – on the race track, the Ohlins DFVs performed without issue, the suspension was stable at all times, even though I now think the springs are slightly soft after all. Well, that will be taken care of at the first rebuild. Amazing when the engine and suspension are working well, really highlights the weaknesses of my car - lack of a proper LSD (both front and rear) and bigger brakes. or perhaps a brake cooling issue. Water temp did not get beyond the halfway point, and on the cool down lap came down to 1/3! Oil never exceeded 100C, so the oil cooler is working well too...

It amazes me time and time again – no matter how well you think you have your car set up, at the track there is ALWAYS something that happens and becomes a take home lesson…

Some fun photos:
Check out Tobe-san in his UNISIA JECS replica R32 DRIFTING in this corner!

The 1000HP JUN tuned R33

We started the session like this:

But I found myself easily passed by Miguel right after the above photo was taken. Took a while, but eventually caught up to him, here I am attacking the first corner, with Miguel right in front of me:

It's not a race, but slower traffic DID slow him down:

Coming out of the 100R, into the left turn:

Passing Montage:

Whoever said that R32s were faster on the track?? It's all driver skill, baby!!! :)

Saturday, April 24, 2010

Ohlins DFV Report, Part 1

There seems to be some interest building on the forums (GTROC UK in particular) with respect to the DFVs for use on second generation GT-Rs. Now, I’m no suspension expert, and with the GT-R I’ve only had the stock, the Nismo S-Tunes, and now the DFVs, so obviously have very little experience in making comparisons, but at least here are my impressions.

Here's how they appeared on Yahoo Auction:

Installation, I had the DFVs put on last weekend (Sunday), and the car’s alignment done, at KTS Heiwajima – a fairly well known shop, close to Nissan Shinagawa! http://www.kts-web.com/tenpo/index.html

Here is picture at night (sorry for this, I was going to pick up my car after the work was done...)

And here is how it looks, installed:

Anyway, my impressions:
Simply put, these are amazing! Could immediately tell the difference in ride quality. It's very firm - more so than the S-tunes - but at the same time, the ride is really, really smooth! The dual valve setup really does a great job - it's unbelievable how the tires can now soak up all the minor imperfections in the road, but at the same time, I feel even more planted on the road than before.

The initial setting was in the middle (I think 12 of 20), and was just about perfect for me. Just to see what would happen - I turned down the setting to the softest setting (1 of 20) - it got soft, but not too soft. I'd say it would be really comfortable on the freeway, so would be good for long distances I think. Middle would be satisfying on a mountain road - I suspect the hardest setting would be very good during the trackday.

With the S-tunes - they had 5 clicks of adjustability - the difference upon adjusting was noticeable, but not to this extent.

Even my passenger (guy visiting from Finland) could tell the difference immediately.

Interestingly, the steering now has more feedback than before. Remember how I complained that it felt somewhat numb on center? With these fitted, I FEEL a lot more of the road, the steering is much more communicative.

I wonder if that is due to the lightweight aluminum body of the shock - when I handled the Ohlins, vs. the S-tunes - the steel bodied S-tunes felt to me to be at least 10 pounds heavier, if not more! In fact, I found a Japanese blog where a guy actually weighed the differences – http://www006.upp.so-net.ne.jp/gfbnr34/BNR34/OHLINS.html

A difference of 4kgs up front, and 7kgs in the rear!

So I am wondering if the lightweight construction of the Ohlins result in better handling and feel.

It's going to be interesting to see how a lightweight wheel (the RE30s) interact with these DFVs, at their hardest setting.

Stay tuned for my report from the trackday at Fuji Speedway, as I'll recount my on track impressions with the DFV/RE30/S-tire combo!

Friday, April 23, 2010

Carbon Fiber Film (3M Di-noc product)

So for the biannual shaken inspection, my friends Dino and Alex, as they had helped me prep the car, had removed the rubber strip on the bottom of the front spoiler. This had left some ugly glue residue, and further exposed some scratches that the rubber strip had hid along the bottom edge.

What to do? I was tempted to go back and put a new rubber strip on the bottom, but then came across this - which I decided to try out.


Turns out this while the material is made by 3M, it's actually made here in Japan by 3M Sumitomo...for the quality and detail, I am not surprised!

Anyway - I went ahead and ordered a large roll - they only come in one maximum width - but which was not long enough to wrap the front splitter - so I ended up measuring the splitter end to end, and ordered more material than I needed, just in case. I also ordered the recommended primer, to ensure a solid bond to the underlying surface.

Of course, I first wanted to practice, so I decided to use a side sill - easily removeable and fairly small.

Here is a picture of the 3M material before the glue surface is exposed.

In creating this practice piece, I cut a sheet about the same size as the sidesill, plus a little extra on all sides. The most difficult part of this was the "SKYLINE" lettering, which required lots of patience and liberal amounts of heat from the wife's hairdryer. (and this in turn burned my fingers)...

3M also has this primer, used to prepare surfaces for maximum (and permanent) adhesion. As you probably know the Di-noc material is used in construction to simulate stone and other textures, so I guess use of the primer is needed there. I ordered it because, with the splitter in the very front, I wanted to make sure the Di-noc stuck.

Here's how the splitter looked after the primer had dried to a tacky consistency.

Ok, now onto wrapping the splitter itself. You can see I cut out a large sheet, a bit longer on both sides of the splitter itself, and began wrapping. Hard to tell, but I had focused on making the material stick in the center middle area first.

Turned out the sides were difficult. I ended up stretching the material best I could over the air ducts, then focused on getting the material applied to the sides (with no holes) as smoothly as possible.

Resulting in this. Note the intake holes are still covered up.

Finally, with some CAREFUL (but not careful enough!) cutting, I managed to poke through to the intake holes. I purposely cut horizontally quite near the top of the splitter, in order to end up with as much material on the bottom (so people looking down would see the material). What is not visible is that the vertical strake is not covered - I had to cut small pieces and wrap around those to complete the effect.

Unfortunately, stretching the material has its limits. A close inspection of both of the intake vents on both sides will either show some careful patching, or on the right side, some quite poor patching. I plan to fix this later...

But, from a distance, it looks ok.

I wrote up some comments on this material on the GTROC UK forum as well:

Tuesday, April 6, 2010

Surprise and some Re-Wiring

Recently I've begun to think that my car's dampers - Nismo S-Tunes, while perfectly adequate for the road, would eventually require replacement with something more track worthy. At least, higher spec and adjustable - some higher grade coilovers.

Imagine my surpise when this weekend, just after I had spoken with Honda-san and Prince Nissan Shinagawa about an eventual upgrade, I logged onto Yahoo Auctions and found a set of Ohlins DFVs for an unbelievable low price - the first used ones I had ever seen.

The selling owner said he used to have an R33 GTR, and had outfitted the DFVs, only to find the ride harder than he thought. He swapped out, only to discover that the DFVs were better all around, and was about to swap them back when his car got stolen! So, with only about 5000kms, these units were in pretty good shape. After conferring with my friend and suspension expert Sumi-san, I decided to take a chance - after all the price was less than half of buying them new. If they turned out to be duds, then I could always have them rebuilt for about 20,000 yen each. And still pay less than a new set!

So when I got home today, this is what I found waiting for me!

Ohlins does not produce a model for the BCNR33 specifically - however the BNR34 units can be used without issue (I think there is an adapter, I have to check).

After verifying all the pieces appeared to have arrived, I set upon continuing my other project - rewiring the tweeter wiring. When I got the stereo/navi installed when I first bought the car, they had installed the tweeters on double stick tape, on the dashboard. After deciding that the tweeters would look better if I mounted them on the door, I took the door apart, only to discover that the wiring for the tweeters ran on a separate line to the center of the dash.

So doing some research on the Pioneer car stereo website, I found that there SHOULD be a crossover amp somewhere. So today, I decided to delve into the mess of wires behind the stereo, to find them. Appears they didn't bother shortening the wiring, just stuck it all there behind the stereo. What a mess.

After some careful digging, I did find the crossovers - here in clear plastic, with the red capacitors.
What a mess.... yikes...

Once I figured out the wiring that led out from the head unit and connected to the crossover's "amp" input, I disconnected these and connected them to the speaker wires leading to the right door. I then opened up the door, removed the speaker, and connected the crossover to the existing wire harness. Like so:

Tomorrow, I will work on the left side, and then figure out how to securely mount the crossovers inside the doors. Then reassemble the stereo and the wiring (one day I will remove the excess, but not this time around...to keep the larger RCA type cables clean, will have to purchase shorter cables), and put the center stack back together.

Last, I will affix the tweeters to their new location. But this will probably be during the week next week, as this weekend I am determined to do a few things to get ready for the upcoming SSCT track day on the 25th!