bonzelite

on our way to torque and horsepower:

when an object is moved one foot (12 inches) of distance, by applying a force of one
pound (16 ounces), one foot-pound of work has happened.

torque is force, applied over a distance --the "moment-arm"-- to create a rotary motion. so, then, a 1 lb force, on a 1' moment-arm, produces 1 ft-lb of torque.

"work" and "torque" are equivalent.

therefore, a 1 lb object, moving over a 1' distance, in 1 sec, requires 1ft-lb/sec of power --one horsepower is arbitrarily defined as 550 ft-lbs/sec.

in automotive terms, horsepower is the rate of producing torque.
to convert between these two quantities, given the RPM:

HP = (TQ*2.0*PI*RPM)/33000.0
TQ = (33000.0*HP)/(2.0*PI*RPM)

where:

TQ = torque in ft-lbs
HP = power in horsepower
RPM = engine speed in revolutions per minute
PI = the mathematical constant PI (approximately 3.141592654)
note: 33000 = conversion factor (550 ft-lbs/sec * 60 sec/min)

maximum torque and power peaks will not necessarily occur at the same time;
they may occur at different rpm's. generally, any engine will have a maximum HP
at a given RPM.

bonzelite

as is widely known, the GT-R uses a computer-controlled AWD traction system called ATTESA-ETS.and as mentioned earlier, the V-spec version uses a more advanced version called ATTESA-ETS Pro:both systems transfer maximum power to the ground in any given situation.*normally, the GT-R is 100% RWD.

however, when ATTESA detects traction loss at the rear wheels, it will send power to the front wheels, locking progressively up to a full 50:50 split within 200 milliseconds (within 2/10 sec).

bonzelite

Datsun 200SX 80-83 (16-spoke) Cast 14x5.5 15.0lbs
Datsun 200SX 80-83 (32-spoke) Cast 14x5.5 16.0
Datsun 200SX 80-83 (disk) Cast 14x5.5 14.0
Datsun 280Z 79-80 Cast 14x6 18.0
Datsun 280ZX 81-83 Cast 14x6 13.0
Datsun 280ZX Turbo 81 Cast 15x6 17.0
Datsun 280ZX Turbo 82-83 Cast 15x6 14.0
Datsun 810/Maxima 81-84 Cast 14x5.5 15.0
-------------------------------------------------------
Nismo LM GT Magnesium Forged Mg 18x10 17.1lbs
-------------------------------------------------------
Nissan 200SX 84 Cast 14x5.5 15.0lbs
Nissan 200SX 84-87 Cast 15x6 19.0
Nissan 200SX Turbo 85-86 Cast 15x6 19.0
Nissan 240SX 89-90 Cast 15x6 16.0
Nissan 240SX 91-94 Cast 15x6 18.0
Nissan 240SX 95-96 Cast 15x6 15.0
Nissan 240SX 95-98 LE and SE Cast 16x6.5 18.5
Nissan 300ZX 84-85 Cast 15x6.5 19.0
Nissan 300ZX NA and TT front Cast 16x7.5 16.0
Nissan Altima 93-97 Cast 15x6 17.0
Nissan Altima 98-01 Cast 16x6 18.0
Nissan Maxima 85-86 Cast 15x6 20.0
Nissan Maxima 87-88 Cast 15x6 17.0
Nissan Maxima 95-99 GLE Cast 15x6.5 16.5
Nissan Maxima 95-99 SE Cast 16x6.5 19.6
Nissan Sentra SE + SE-R 01-02 Cast 16x6 18.0
Nissan Sentra SE-R Spec V 02 Cast 17x7 24.0
Nissan Stanza 90-92 Cast 14x6 15.0

full listing:
http://www.superhonda.com/tech/wheel_weights.html
and
http://www.wheelweights.net/

bonzelite

KAZUTOSHI MIZUNO
Chief Vehicle Engineer, Vehicle Design Engineering Department No. 1, Vehicle Reliability Engineering Group
Nissan Motor Co., Ltd.

Kazutoshi Mizuno is the chief vehicle engineer at Nissan Motor Co., Ltd.’s Vehicle Design Engineering Department Number 1, Vehicle Reliability Engineering Group in Japan.

Mizuno joined Nissan’s Vehicle Design Department after graduating from the Nagano Technical Junior College in 1972. He has held a variety of positions within the company, including working in the Vehicle Body Design Engineering Department on the Maxima and Sentra, as well as the Body Design Department for the Primera and Skyline. He has also worked as the chief of vehicle planning on the Skyline GT-R and Silvia and chief vehicle engineer on the Z®, Skyline, Stagia and Infiniti FX45.

Racing has also played a big part in Mizuno’s career at Nissan. From 1987 to 1993, he participated in the development of Nissan’s Japan and international Group C vehicles and held several positions, including chief of the technical department, within Nissan Motor Sports International (NISMO). Mizuno was team director for Nissan’s R90/R92 LeMans programs from 1989-92 and director of Nissan’s Japan Domestic Championship R33 team in 1994-95.

more nissan bios at:
http://www.nissannews.com/nissan/200...graphies.shtml

bonzelite

this trove of breaking news articles will keep you current:
http://www.nissannews.com/

a rather significant recent report (at the time of this posting):

Nissan Announces Best April Sales Ever [May. 3, 05]
NNA Achieves a 27% Increase in April Sales Over 2004

GARDENA, Calif. (May 3, 2005) – Nissan North America, Inc. (NNA) reported 91,621 total sales in April, an increase of 27% over last year.* This month marks the best April sales in the history of Nissan North America, as well as the Nissan and Infiniti divisions.* In addition, Nissan models Altima, Murano, Armada and Titan and Infiniti models G35 Coupe, M and FX achieved their best ever April sales.** The Infiniti M has achieved its best sales month to date.

bonzelite

motion parallax - cue to distance in visual perception, which depends upon the fact that when the perceiver is in motion, objects which are at a greater distance appear to move more slowly than objects that are more nearby.

this becomes increasingly relevant when larger objects in the distance appear to be moving slower, giving the illusion that they are crawling along. this failure in perception is what so often kills people at railroad crossings, as they think the train is moving far slower than it really is. recent installations of flashing lights to the fronts of trains has aided, yet has not fully remedied, this vexing and sometimes fatal situation.

i would imagine that owning a GT-R would help to outrun any train, or anything in general, on the ground, further negating the ill effects of motion parallax.

bonzelite

back at the ranch, remote texas desert, 1970:

at a time after their corvair tests, jim hall, hap sharp, and GM engineer frank winchell (developers/inventors of the rear deck spoiler in 1966), began experimenting with low pressure zones under the length of the car. they found that by adding, laterally, devices to the sides of the body near the ground, a reduction in air pressure under the car was generated enough to literally suck the car to the pavement.

their "sucker car" (model Chaparral 2J) reached cornering speeds of up to 1.7 g, was soon considered too dangerous, and was eventually banned from racing. however this innovation in automotive downforce technology became known as "sideskirts."

bonzelite

wet vs. dry:

we've all heard it: wet and dry-sump. in our case, the sump is the collector at the bottom of the engine that collects lubricants for redistribution: the oil pan. this is the sump.

the wet setup is used in passenger cars, and mostly in lower levels of racing. "wet- sump" means engine oil is collected and stored in the oil pan until it is pumped back through the engine.

a dry-sump immediately sucks, scavenges, the oil that is collected in the pan to an external tank before being recirculated. because this sump does not actually store the oil, it is referred to as “dry.”

a dry-sump has several advantages over wet, the main one being additional power: because there is only very little oil actually in the pan, friction or "windage" --oil sticking or splashing against the rotating crank --is greatly reduced. with a reduction in this friction, less horsepower is lost in the drivetrain.

also, as oil in the dry setup is sucked out of the pan, this process creates a vacuum effect inside the pan that "seals" the crankcase --further increasing horsepower by improving ring seal, raising compression.

other perks of a dry system are: greater oil capacity because most of the lubricant is stored in an external tank, away from the sump; the ability to easily add remote oil coolers (once in a while, you will run across a photo of a GT-R with a mini radiator-looking thing mounted into the grille area --this is an oil cooler, and, more than likely, is part of a dry-sump system on that car).

also, because a dry-sump pan does not store oil, it can be quite shallow to allow for lower engine placement, lowering the center of gravity and improving handling balance.

bonzelite

the brakes have been hot all day, and again the spirited driver accelerates aggressively, perhaps, then throws the car into a turn. unexpectedly, a lumbering SUV with the driver on the cell phone appears from nowhere, and the brakes slam: the fluid in the lines and master cylinder immediately boil: air bubbles form, rise to the top, burst, and air is cycled through the fluid again and again. all in nanoseconds.

with accelerated heart-rates, the drivers realize there was no accident, recover themselves from the incident, and go about their seperate ways. no harm done.

but not exactly: not only are there air pockets in the lines, there is moisture as well, as brake fluid is hydroscopic (glycol-based, similar to ethylene glycol, ie, anti-freeze). that is, it takes on moisture anyway, over time. this moisture in the fluid will boil as heat is transferred from the hot brakes to the brake lines. the more moisture that the fluid takes on from the air, the more moisture there is to potentially boil again. and the fluid degrades over time.

because you are reading this on a GT-R forum, you are likely more apt to boil brake fluid than most drivers, as you probably push the envelope of your brakes' threshold of pain more frequently. so instead of once a year, change the OEM brake fluid (most likely a "DOT 3" 401F-boiling, glycol fluid) every six months. like once at thanksgiving, and again on memorial day.

or, to ensure safe-stopping, put in a DOT 4 (glycol 446F-rated), or a silicone-based, "non-boiling" DOT 5 fluid (500F boiling point if small amounts of moisture enter the system).

however, DOT 5 is not water-soluable. and if significant amounts of water do manage to invade the brake system for any reason, it will not mix into the synthetic suspension of the DOT 5, will collect at the lowest point, and will boil at 212F --far lower than DOT 3-4 (even with a 3% moisture saturation, DOT 3-4 will still hold up until 300F). if this water glob boils at or near the caliper, that device will fail, and there will be "vapor lock;" zero braking ability at that location. so much for DOT 5.

DOT 5 is good, however, for -40F.

if you change to DOT 5, don't change back to DOT 3-4: you will never get all of the silicon out of the lines, and it will glob up, leading to system failure.

DOT 5 is mostly used by the military, and largely not taken into account by current automotive engineers.

also, avoid petrolium-based products in the brake lines: motor oil, power steering fluid, mineral oil. these will destroy rubber seals.

bonzelite

to use the engine's compression to slow the car instead of the brakes:

1. disengage the clutch (push the pedal down): this disengages the gear box from the driveshaft (the engine).

2. put the tranny into neutral

3. engage the clutch briefly: this doesn't transfer any power to the wheels, but merely gets the gears up to wheel speed. you may also have to "blip" the gas a bit, depending on the situation.

4. throw the shifter into whatever gear you want: since the gears are now moving at approximately the same rpms as the wheels, there's only going to be a little grind as the two spinning gears meet and mesh.

5. re-engage the clutch and go.

do all of this very quickly.