Carbon Fiber Bumper Exhaust Surround, Renewal

So if you've seen pictures of the rear bumper of my car, I've had this thin dry carbon fiber exhaust surround I found on Yahoo Auctions back in 2008!

With the newly installed Tomei ExPreme Exhaust

Obviously, the goal here is to protect the bumper from all the soot the RB26 engine spews out.

Long-time readers know that my car was used as the jig to develop the exhaust, and that this shot
  was used for their catalog

While it still looks great from a distance, I was becoming aware that the heat of the exhaust, as well as it's location on the rear edge of the bumper, was wreaking havoc on the carbon.

A close-up reveals these flaws.

But that's ok... it's much easier to remove and replace this piece, than to have the bumper touched up. In fact, I took the piece off before I had my car detailed, so that all the surrounding areas (and underneath) could be properly cleaned and protected.

 I then went back to find the vendor on Yahoo Auctions, 5000 yen and 3 days later:

Old one obviously the one not wrapped up.

Here you can compare directly. Camera angle shot makes old one on left look larger.

As you can see this carbon is really thin, but since it's not bolted on, replacement is an easy affair. Just take off the old one, clean the bumper (I had taken it off before the detail at RAPT), then simply slap back on using the double stick tape.

You can see the remnants of the tape on the old one on top.

Like this:

Truth be told the tape is old and I may need to readjust later

Make sure the area around the exhaust is clean:

A quick wipe with a microfiber towel, then

Peel off the backing of the double stick tape, then slap on making sure one edge slips between the bumper and the spat:

Easy!

Later, after a quick drive:

Can't even tell it's been replaced.

Oh, and I dropped into Nissan to order some minor bits so I will have another update on this blog soon!... stay tuned and thanks for reading!

Thomas Mangum's Midnight Purple R33 GT-R - Spec Check and Driving Impression! (Part 2)

So once I had checked out the exterior of Thomas Mangum's 3H tuned R33 GT-R and talked about the mechanical bits, it was time to go for a drive.

First however I did a quick check of the interior.  Thomas' car has some interesting bits, although as interiors tend to be even more expressive of individual taste than exteriors (because interiors aren't as visible), my thoughts here might be a bit more subjective than usual.

Even though Thomas' car is a 1995 Series 1 (zenki), he has changed out the interior for Series 3 (kohki) bits - this means instead of the usual blue accented seats and door cards, he has the red accented seats and door cards.  To be honest, somewhat incongruous given the lack of a passenger airbag. But a minor "gripe" I guess (I suppose I'm a purist...)

Note red dotted door card. Momo steering wheel with the Nismo horn button.
You can also see his Greddy OLED boost controller mounted to the left of the steering column.
Those with sharp eyes will see the Bee-R rev limiter mounted below that.

Obviously an immediately obvious difference from my car are the white faced NISMO gauge clusters.  While I thought it would prove distracting, oddly enough it didn't bother me at all! In fact I can see how this might be better during the day, at least from a visibility perspective.

No airbag is giveaway for Series 1... got some interesting carbon-like pieces there though.

Looking closely, you can see 3 different carbon fiber patterns.  The main fascia is actually an extremely rare, OEM option, carbon fiber print-like fascia.  The carbon pattern on the shift surround however is a clear print, and the driver's side door switch panel is carbon wrapped. Not for me, but an interesting collection!

More interesting however are the Nissan OEM optional knee bolsters:

For right knee

These parts rarely pop up on Yahoo Auctions, and so usually the sellers ask for lots of yen. Clearly good if you value bracing yourself during hard cornering over hearing the output of the driver side door speaker...

For left knee

Finally, this was cool - a genuine Top Secret shift boot! With the shifter capped off with a Tomei shift knob:

The NISMO plaque is an add on...

SO...putting aside the interior aesthetics and my subjective commentary on it, how does the car DRIVE?

Ok well the first thing I noticed was the Series 3 transmission Thomas installed - in a word, superb. I was blown away by how the shifter is so direct and precise - of course not in the league of the NSX I drove a while back, but way better than the gearbox I had in my car (before GETRAG).  In fact, even compared to the GETRAG now installed in my car, being totally honest with myself, I'd have to say I prefer how this feels - a no-slop, no-slack, extremely direct gearbox - not as heavy feeling as the GETRAG either.  Thomas told me he has a short shift kit but it must be the NISMO Quick Shift (with a 25% shorter stroke), I previously had the NISMO Solid Shift (only 10% shorter stroke) but it did not feel like this!

Second thing I noticed was how hard and stiff the suspension was as I drove around town. Usually this is something that one notices as a passenger, not as the driver.  "Don't worry" Thomas said with a grin from the passenger seat, "You'll see how it all smooths out on the Wangan."  The car is running Greddy S Spec Full tap dampers, with spring rates of 10 kg-m front and 8kg-m rear - this is a custom set up he selected, seeking the best balance between livability on surface streets and control while blasting on the Wangan. And he was right - when we later took the car on the expressway, the car not only felt stable, smooth and responsive, but the balance was superb.

Speaking of balance, one area which I thought could be improved was the brakes. This car runs F50 Brembos up front on 355 millimeter BIOT 2 piece rotors (Endless brake pads), and the OEM rear Brembos using custom brackets on 350mm VQ36 Skyline rears rotors (Project mu pads).  If you recall from when I installed the R35 brakes on my car, old thinking was the need to have bigger rotors up front with smaller in the back. More recently the thinking is that, having the rear rotor almost as large as the front can only help and in fact contribute to more stability. Nissan apparently realized this during the production run of the RB26 GT-Rs, which is why the last R34s had larger OEM rear rotors.

In fact this set up is now a popular conversion in Japan, giving great stopping power at a very reasonable price,  although you will need 18 inch wheels (which most people upgrade to anyway) as this combo is too large for the stock wheels.  Stopping from speed wasn't a problem in this car, but not sure if it's the inherent front brake bias, or the different pads, or the lack of a digital G-sensor (its function affects the braking as I discovered), but I just felt there was too much emphasis on the fronts - not necessarily a bad thing but subjectively not what I am used to anymore.

Finally, two areas where this car has a very different personality from my car - the handling and the engine power delivery.

Driving around town, the handling didn't seem too different from most GT-Rs I've driven. And it wasn't that different when making lane changes on the expressway.  It was when I was making a sweeping right turn at about 60kph, getting onto the expressway, when I noticed how the rear end of the car felt more planted and direct than mine.  Hard to describe but it was almost an oversteer effect, meaning that the fronts could focus on getting the car through the curve as quickly and neutrally as possible.  Thomas believes this is a result of having SuperPro bushings all around, I think it might be his rear camber at -2 degrees (according to Thomas) as well as how he has rear roll center adjusters installed.  It also might be his disconnected Super HICAS, although I've driven other cars with locked out rears and suspect the camber angle as most likely the reason for this rear end agility.  Anyway, this experience has inspired me to start thinking of upgrades to my car in the same way!

Finally, the engine.  Obviously I was curious about how the V Cam was going to affect things. Since I hadn't driven his car BEFORE he installed the V Cam, I can't give a direct comparison, but with the larger 2530kai turbos, I expected that the car would have suffered from turbo lag and then boom!  When I asked Thomas, he did confirm that before he'd find himself having to shift down from say 5th to 3rd, to raise the RPMS, in order to get enough torque by engaging the turbos (which came on full at about 4500 rpm he says). Not only did this cause him to end up working with a very small rev range (before having to shift up) but the sudden increase in torque would cause his rear end to violently swing out on occasion.

Driving it now, the V Cam is programmed to kick in smoothly and provide enough torque down low such that the transition from the V Cam to when the turbos kick in is seamless.  In other words, the engine feels like a much larger engine with a gradually increasing torque from lower RPMs reaching a maximum torque value somewhere in the 5000rpm range.

I've heard that with V Cam, it makes the smallish RB26 feel like a larger engine - and now I get it.  At least on the bottom end, Thomas' car DID feel like it had a larger naturally aspirated engine. Of course once the turbos kick in it still has the GT-R flavor.

Finally, while I did not drive the car at night, Thomas later sent me this photo to show off his LED upgrades to the gauges. This guy is REALLY into purple....

And so the purple motif continues even at night...

Thank you very much Thomas for the opportunity - it's given me some inspiration for my car but also  reassurance that my car is in good shape as well.

Stay tuned as I have some minor tweaks coming up very soon!

Thomas Mangum's Midnight Purple R33 GT-R - Spec Check and Driving Impression! (Part 1)

So recently my friend and fellow R33 GT-R fanatic Thomas Mangum invited me to drive his Midnight Purple machine.  I jumped at the chance – it would be a rare opportunity to drive a high spec car (and one with the HKS V Cam, too!) and compare against mine. 

When I pulled up to his house, I initially took some photos before jumping into the driver’s seat.   Thomas seemed embarrassed by how dirty his car was, but that couldn’t be helped as it’s parked outside and as a daily driver a car cover doesn’t make sense (for most people...).   Nevertheless the car was in good shape, nothing a nice wash and wax wouldn’t fix.

Purple disc rotor caps to match the Midnight Purple car. Nice touch. F50 Brembos with Biot 2 piece rotors!
Wheels are ENKEI RS05RR in 18x11J(!!!) with offset of 16.

A bit of trivia about these wheels - these were one of, if not THE first, sets of the RS055RR that Enkei made for the Skyline GT-Rs. How do we know? Because when Thomas and I went to Tokyo Auto Salon  that year, we noticed that the displayed wheels had some stickers that these wheels did not have. When we inquired, we were told that the first batch did not have the stickers, and further all the ENKEI reps there said they had never seen or known of a GT-R with them before! (ENKEI later mailed him the missing stickers!)

Essentially this is a custom made front bumper - I've never seen another quite like this.

I recall when Thomas asked me if I had ever seen this front bumper before when it came up for sale on Yahoo Auctions a few years back... obviously the answer was no. It seems to be a very clever design, incorporating cooling abilities along with the front canard aerodynamic effect.  It apparently was a one-off design for one of the JUN Auto racing cars [thanks to our friend Matt Rearick who remembered seeing the same item on Yahoo, and the description!] which meant that Thomas had to get clever to incorporate turn signals in order to make it street legal.

AutoSelect Tower Bar. ARC Cooling panel (no longer made).
Aluminum catch tank and UK GTROC Aluminum fuse box cover

I'm proud to say I did my bit to contribute to this engine, as the fuse box cover was something I gave Thomas a long time ago... Note also the relocated power steering pump fluid reservoir.

Aha! V Cam. I can only dream at this point. With a NISMO surge tank too!

Yep. I was eagerly looking forward to how differently this car would drive with the V Cam, given the HKS 2530kai turbos the car is running.

Carbon fiber hood (or bonnet in the Commonwealth?)

He has some interesting custom mods so I took photos of those. For example:

Custom carbon piece to direct air towards the intercooler. If well done, stuff like this adds to a car's allure and personality.

I've already pointed out the clever use of side turn signals used upfront. Here's another custom application:

Another interesting tidbit - oil cooler located here!

Due to the design of the bumper, Thomas couldn't place an engine oil cooler in the usual place (that is, under the left front lights in the front bumper). So naturally, he put this Greddy one up front behind the grill to ensure lots of airflow. Reminds me of the old NISMO set up (albeit that was underneath and behind the front lip spoiler).

Speaking of spoilers:

Genuine NISMO dry carbon 2 piece blade. Looks like the previous owner liked to advertise that fact.

For the back, he found a used NISMO 2 piece dry carbon spoiler blade.  He restored it best he could but you can still make out where someone had applied a NISMO sticker. (and yes, the blue car in the back ground is the ISF I'm slowly modifying...lol)

90mm AMUSE titanium exhaust. 

Thomas' car is equipped with this Amuse R1 titanium exhaust, which obviously maximizes exhaust flow and doesn't even pretend to really have any "muffling" capacities. This thing is LOUD!

Thomas later sent me a list of the specs of his car. For example, some highlights of the engine/powertrain are:
- N1 block bored to 86.5, N1 oil pump, N1 water pump
- Carrillo rods, Mahle pistons (both save weight)
- balanced and straightened crank by NAPREC
- NISMO crank and conrod bearings
- NAPREC high response head kit (ported, etc.)
- NISMO 600cc injectors/NISMO fuel pump
- R35 AFMs
- Tomei Powered oil pan baffle/metal head gasket (1.2mm)/timing belt
- Trust/Greddy Type R intercooler
- Okada Plasma Direct ignition coils
- HKS hard piping kit
- Advance 130A alternator

This is all managed by a custom flashed ROM that piggybacks on top of the OEM ECU. Thomas estimates about 600 horsepower. 

So how does this all add up, really? I’ll give my honest (good and bad) impressions on how the car drove, as well as photos of some interesting interior bits, in my next post...