|
You are not currently logged in
Appendix Z
Material presented in the FAQs have been compiled, edited & reformatted
to be as concise as possible.
2+2 / 2+0
2+0 : Also known as a coupe. Two front seats, no back seat
2+2 : Two front seats, two (small) back seats
How to recognize them...
The 2+0 has the fuel trap in FRONT of the rear left wheel, while the
2+2 has the fuel trap AFTER the rear left wheel.
The following info is only about models that can be bought through local
dealerships (not converted, not privately imported)
In the US,
- ALL the 2+2 ARE NA, there was no 2+2 TT imported.
- The 2+0 can either be a NA or a TT
- Convertibles are based on the 2+0 model
In Europe
- ALL the 90+ are 2+2 AND TT
- The 2+0 are not available
- The NA are not available
In Japan (not absolutely sure about this...)
- The 2+0 can either be TT or NA
- The 2+2 can either be TT or NA
Henri Le Hir
AIV valves
The AIV function, as described in the manual, is to send secondary
air to the exhaust manifold using a vacuum created by exhaust pulsation
in the exhaust manifold. When the exhaust pressure is below atmospheric
pressure, secondary air is sent to the exhaust manifold. When the exhaust
pressure is above atmospheric pressure, the reed valves prevent secondary
air form being sent back to the sub-air cleaner. I've heard that de-acceleration
is supposed to keep the assembly clear of water.
Eric Rahkola
As for the AIV (air injection valves) "gurgling", they are in the front
fender wells behind the plastic shielding at the rear of the front tires.
Very few 90-92 ZXs have escaped a failure of these. Symptoms include the
"gurgling" sound at idle that stops just off idle and returns on decel
back to idle. Also the car will fail the idle portion of most smog inspections,
since the ECU adds 7% more fuel when they operate so
the extra air they pump to the catalytic converter has some fuel to burn
to keep the cat up to temp. If the AIVs are not sucking air into the exhaust
the fuel just passes through making things worse then ever. The fix is
to try to clean and align the reeds in the AIVs, replace reeds, or replace
the AIVs as an assembly.
Jim Wolf (from his only known forum post!)
ALC-Automatic Line Controller
The ALC is a product made by HKS and ALC stands for: Automatic Line
Controller.
The ALC was developed for the computer controlled automatic transmission
as equipped on the Z. It is designed to maintain line pressure within the
transmission for consistent, high performance shifting.
Kyle(Houston)
Boost
The amount of positive air/fuel mixture pressure inside the intake.
Usually measured in pounds per square inch (PSI), but sometimes measured
in barametric (bar). Alternately, a negative intake pressure is vacuum.
Dallas DamonZ
Boost Jets/Welding Tips
Calibrated Boost Jets come with the Jim Wolf ECU
upgrade. They are simply small orifices to restrict vacuum pressure to
the turbo wastegates, causing the wastegates to stay closed until a much
higher boost pressure is achieved. The power gained
from the ECU upgrade is from the boost jets, not the ECU. The ECU is remapped
to provide adequate air/fuel mixture to the engine under the altered boost
levels.
Dallas DamonZ
Contact Welding tips are originally used to meter gas on welding guns,
but can be used in place of boost jets. They are metal, not aluminum like
boost jets, so are a bit easier to work with since they are sturdier.
They can be bought at any welding supply shop in different metering
hole sizes, such as 0.045 inch, 0.035, 0.030, and 0.025 inch. since they
came in many sizes, boost level can be fine tuned to your requiremnent.
***Caution***
Remember that a Jim Wolf ECU upgrade makes the raised boost safe, but
boost can be raised on a stock ecu up to about 14 psi if you use it sparingly,
i.e.: no top speed runs, etc. It is also of prime importance to always
have an accurate boost gauge (non-stock) on the car and use cooler
pfr6b-11b(#6) NGK plugs or pfr6b-11 plugs to help ward off detonation.
The boost limits of the stock injectors is 15.5 psi per Jim Wolf.
Chris(Miami)
Cats
Catalytic convertors are devices used in the exhaust system to reduce
pollution of the environment from unstable hydrocarbons from the emission.
They contain some catalysts (like vanadium or platinum) that neutralize
unburnt hydrocarbons into carbon di-oxide and water.
Cars with cats (after 1975) should only use unleaded fuel as the lead
(Lead tetra-ethyl was added to gas to reduce knocking and to lubricate)
in the gas will coat the catalysts and make them inoperative.
Kam
Cat-Back Performance Exhaust
An exhaust from your main catalytic convertors
back to the mufflers. Most cat back exhaust are 2.5 inch to 3 inches in
diameter. Depending on your needs, anything above 500 horsepower should
have a 3 inch system so the air can flow much faster. Prices for a cat-back
system can range from about $400-$900, depending on who the supplier is.
However, you can have a custom built cat-back system using a 2.5 or 3 inch
pipe with the mufflers of your choice, or you can purchase a complete system
from any major supplier which will include not only the pipes but the mufflers
also. Most cat-back exhaust system are built to achieve maximum power from
an engine by letting the air flow much quicker and smoother... Hence most
aftermarket exhausts use mandrel-bent pipes which allows the air to flow
quicker and smoother. Power gained from an aftermarket exhaust is best
determined by a dyno, but in most cases expect about 20-30 more horsepower.
Choosing an aftermarket muffler not only depends on the about of horsepower
gained but also on the way it SOUNDS!!
zlemard
Chip
Cold plugs
Used in cars that will see harder use since the combustion temperatures
rise and promotes detonation.
The lower the #, the hotter the plug.
The stock TT plug is a #5. Typically, colder plugs are used when raising
boost in the TT's. PFR6b-11B is the part # for the #6 plug and PFR6B-11
is for the #7.
Colder plugs aren't generallly used for the N/A Z's since they do not
heat up their combustion chambers as much as the TT's.
Chris(Miami)
CAS - Crank Angle Sensor
Known in the service manual as the CMPS - Camshaft Position Sensor.
The CMPS monitors engine speed & piston position to send the data to
the ECU. It's basically a disc with 360 slits cut in it around the perimeter
& 6 slits cut to mark the 120 degree positions. It uses photodiodes
to transmit light through the slits while rotating to determine speed &
angle.
Dallas DamonZ
www.nhtsa.dot.gov
Service Bulletin #: FC0004794
Date of Bulletin: Jan. '91
Model: 300ZX
Year: 1990
Summary: Excessive initial timing advance, index notch on camshaft damaged,
R/R crank angle sensor, camshaft and cylinder head--1990-91 300ZX CM
The problem was that the left cylinder head of a certain production
# range of early Z cars ('90) was mis-machined. This caused the CAS to
be thrown off in its readings of cam timing, so the symptoms are usually
very sluggish performance or detonation. Eventually the readings of the
CAS stray so far (for reasons unknown to me) that the symptoms show up
when the cars have some mileage on them. I've heard of some having this
problem and they replaced the CAS, but the CAS was expected to fail again,
because the root of the problem is the badly machined left cylinder head.
Chris(Miami)
Detonation
When increasing boost, there is a danger of detonation.
Detonation occurs when the compressed air and gasoline ignite due to the
heat of compression before the spark plug sparks. This results in a loss
of power (at least) or blowing holes out of the side of the engine block
(very bad). Higher octane fuel has a slower burn rate, and is less susceptible
to detonation.
Joe VA
Detonation Sensor
The detonation sensor (or knock sensor) is a piezoelectric sensor that
detects detonation noise below 3500rpm and sends a signal to the ECU.
If detonation is detected below 3500rpm the ECU will cut the boost
to 7psi and retard the timing in order to protect the engine. Any detonation
above 3500rpm will not be detected by the detonation sensor and the ECU
will not
protect the engine.
The detonation sensor is mounted to the block between the heads. To
replace this sensor the engine has to be removed ($$$$).
Kyle(Houston)
Downpipes/Testpipes
The purpose of down and test pipes is to reduce the flow restriction
imposed by the catylitic convertors.
Down pipes are hollow pipes used to replace the restrictive pre-cats
that come right after the turbos on TT Z's. They sell for about $500 for
stainless steel units.
N/A Z's do not have pre-cats. most people do not keep the pre-cats since
they are easily gutted when the clutch is changed or the trans is dropped.
Test pipes are hollow pipes that replace the two main cats under the
car. The main cats can be hollowed out for similar effect.
***This is not a legal modification in the U.S. for street-driven and
registered vehicles and should only be done when the car is an off-road
track car. Getting caught carries high penalties.***
Chris(Miami)
On a Stage III TT, gutted/removed pre-cats can gain 10-15hp & gutted/removed
main cats can gain 10-15hp too.
Dallas DamonZ
Dual POP Charger
Only Useful if the TT engine is producing 450 or more HP.
The kit consists of TWO POP chargers installed
side by side where the air intake was. The MAS will
be relocated on one of the side, while the other will only have a tube.
(If the car already has a POP charger, only the required parts will
be needed)
Because the MAS will only see HALF of the air going to the engine, the
ECU will have to get a new EPROM
programmed to handle the change.
The low speed driveability may suffer, and the JWT "low speed driveability
update" should be installed (comes free with the DUAL POP charger). Installation
of the "low speed driveability update" will required to cut some vacuum
lines, drill a hole in the right stock surge valve, and route a hose to
it.
Henri Le Hir
ECU
Acronym : ECU = Engine Control Unit.
Location : Under the passenger's foot well, under the wooden board.
Function : This is the "computer" that is controlling all the engine
functions.
Notes : When you put a "performance" upgrade, you'll have to change
the "software" in it. The software is stored in an EPROM.
Henri Le Hir
EGR
This is a valve on the engine that goes from the exhaust manifold to
the intake manifold, controlled by the ECU. When the
ECU senses that there is too much oxygen in the exhaust, it diverts some
exhaust gas into the cylinder, reducing the oxygen in the cylinder, causing
more total ignition of the available oxygen and gas, and reduced emissions.
Joe VA
EPROM
Acronym : EPROM = Erasable Programmable Read Only Memory Also known
as a "chip".
Location : Inside the ECU which is under the passenger's
foot well, under the wooden board.
Function : The EPROM is an electronic component where the software running
the ECU, and the data about the car (i.e. maps) are (semi) permanently
stored. Most of the modification that can be done to a Z are through some
optimization of this code, and the modification of the data.
The EPROM is kind of a "silicon floppy disk"
Notes : The EPROM is a 28 pin "chip" that has the software code to run/manage
the engine stored on it. When you upgrade your "chip", you are actually
buying a new/modified EPROM with different "software" on it.
In the case of Jim Wolf Technology (JWT) the code has been SUBSTANTIALLY
changed. In the case of SuperChips, only ONE byte on the entire EPROM is
different (removal of the speed limiter).
Henri Le Hir
EVC
This aftermarket modification controls the level of turbo boost
in the Z. This is attained by a solenoid which sits in the engine bay that
is connected 'through' the boost line (it goes in between the intake and
the wastegate on the turbo.) The EVC's solenoid stays closed which doesn't
allow the wastegate to see the pressure that is really building up (it
thinks boost is low so it's staying closed also). Then, at the last second
(once desired boost is seen by the EVC), the EVC solenoid opens, and the
wastegates slam open and shut again (I think this takes like a nanosecond,)
and this is what allows the EVC to keep rock-steady boost at a pre-programmed
level.
Michael (Topeka)
Fascia
Basically, this is the front bumper on a 300ZX. A stock TT fascia will
have intercooler "gills" underneath the turn signals. Along with
the wing, this is the most popular body molding upgrades. Many companies
make aftermarket front fascias for both NA and TT models.
Greg(Dallas)
Fairlady Z
The Short Story:
Fairlady - The name given to the first line of sports cars designed
and built by Nissan Motors Japan after W.W.II, with the specific intent
of being marketed in the USA - 1960.
The name "Fairlady" was given to the new sports car line by Mr. Katsuji
Kawamata, President Of Nissan Motors Japan, after he attended the Broadway
Musical "My Fair Lady" while visiting the US in 1958. He felt that
the name would invoke an image of beauty for the car - because people would
think of the beauty of the music and the leading lady in that Broadway
Musical.
This is a common and accepted practice within the Japanese culture for
selecting automotive names. It is not a usual cultural method here
in the US however - so Nissan more commonly used engine size and model
numbers as Model Names for the US market. (Note There are also minor
differences in many cases related to engine sizes, safety and emissions
equipment between the Japanese home market models (Fairlady Z's) that thoes
exported to other countries)
Carl Beck
Gutting the Cats
To remove the catalytic material from inside the exhaust, this allows
much freer flow of the exhaust gasses. Gutting all four can gain ~22hp
on TTs. NAs should retain their cats to keep enough backpressure for optimum
performance, TTs get backpressure from the turbine side of the turbo.
Dallas DamonZ
H-Pipe
A style of exhaust pipe between the main cats & the mufflers sections.
The left & right side pipes are joined with a center pipe in an 'H'
fashion for balancing the exhaust pressures before the mufflers.
Dallas DamonZ
HICAS
Acronym for: High Capacity Actively Controlled Suspension.
Method by which all 4 wheels are steered based on information processed
by the HICAS control unit with the main input being vehicle speed.
For some detailed info: click
here or get "Nissan 300ZX: An Enthusiast's Guide" by Ray Hutton (of
C&D fame)
Kam
Injectors
Small solenoid valve that injects atomized fuel into cylinder. Signal
from ECU causes coil in injector to energize, pulling
a
pintle back from the tip of the injector, allowing fuel to spray out.
The duration of the spray is varied by the ECU depending
on throttle position, RPM, etc.
PWS
Intake
Intercoolers
Turbochargers compress air. From PV=nRT, the only other variable is
temperature. When boost pressure goes up, so does
temperature. Hot air is less dense. Intercoolers cool the air, making it
denser, creating more burnable oxygen per unit, equalling more horsepower.
Larger intercoolers work better, making more hp.
Joe VA
MAS
MAF = Mass Airflow Sensor
A device which measures the amount (mass) of air inducted into the engine.
This measurement is used by the ECU to calculate the
amount of fuel neccessary for complete and safe combustion.
Gonzalez
NA/TT
NA (Naturally Aspirated) - Non-Turbo version of the Z. 10.5:1 compression,
222 horsepower stock, 225/50-16 stock tire size, 16x7.5 stock wheel size.
4.08 rear differential ratio. Available in convertible, 2+2, t-top, and
slicktop.
TT (Twin Turbo) - Turbocharged version of the
Z. Compression dropped to 8.5:1, 300 horsepower stock, 9.5 psi boost
from the factory. Same tire/wheel combo in front, but with 245/45-16 on
16x8.5 wheel in the back. Front fascia changed for
intercooler slots. 3.69 rear differential ratio. Heavier clutch & clutch
vacuum booster, Super HICAS rear wheel steering, t-tops,
rear spoiler/wing, TwinTurbo sticker on rear right side, adjustable suspension,
& dash cluster boost gauge are all standard equipment. See 2+2
/ 2+0 for more configuration specs.
compiled from: Henri Le
Hir & MikeeZ
NOS-Nitrous Oxide System
Nitrous Oxide is a gas. It's properties dictate that it burns faster
and hotter than oxygen. A NOS system sprays Nitrous Oxide into the air
stream coming into the engine (before it gets to any of the 6 cylinders,)
this then mixes with the air coming in and gets drawn into the cylinders.
More power is provided because of the faster and hotter burning of NOS
compared with the air it's mixed with. NOS systems usually draw quite a
concern about the added stress it puts on an engine (and it really does
pack quite a punch when released.) But, the VG30DE engine in the Z is quite
a strong one and withstands this quite well. Nevertheless, caution (and
moderation :) should be taken in using any Nitrous setup.
Michael (Topeka)
O2 Sensors
The O2 sensor's purpose is to read how much oxygen is present in the
exhaust. This signal is sent to the ECU. This signal
is used to tell the ecu how rich or lean the air/fuel mixture is so the
ecu can adjust how much fuel the injectors inject to achieve as close to
a 14.7:1 stoichiometric air/fuel ratio, which is neither rich nor lean
and produces good power and fuel economy.
Chris(Miami)
PCV-Positive Crankcase Ventilation
The purpose of the PCV valves is to relieve pressure that might build
up in the engine (crankcase). This pressure can arise due to a slight amount
of pressure (from the fuel burning in the pistons) "leaking" its way past
the piston rings, into the crankcase.
Excessive pressure can cause engine oil seepage past the engine seals,
especially the main rear seal, out of the engine, where it may slightly
leak to the ground, or be burned on the exhaust pipes.
Gonzalez
Plenum
The plenum (or upper intake) is the upper piece on the engine that
is connected to the throttle bodies. The plenum is what separates the air
to go into the lower intake and then to the intake runners on the heads.
Kyle(Houston)
POP Charger
POP=Jim Wolf Technology's Performance Optimized Programming. This is
a cone air filter/intake 'velocity stack' that replaces the stock air box,
reducing induction restriction, and give some extra horsepower and fuel
mileage. It either comes with a K&N filter (Stillen) or a generic one
(some JWT), both of which are washable
Joe VA
Power Transistor Recall
The power transistor is the unit that amplifies the ignition signal
to each of the 6 individual ignition coils. The early Hitachi ones on 90'
and 91' Z's were prone to failure so Nissan made a voluntary recall on
them to replace with a new improved Mitsubishi unit.
The symptoms of a bad power transistor are stalling and running rough.
Many times, the car will not restart once it stalls. Nissan is to pay for
towing as well as the part since this is a recall.
A few of the replacements have failed as well, so Nissan should pay
to replace the faulty transistor again.
Call 1-800-Nissan-1 with your VIN # handy so you can find out if the
recall has been performed on your Z.
Chris(Miami)
Even if the Power transistor is exactly the same all around the world,
Nissan decided that ONLY the US Z can benefit from the recall !
So if (or more exactly when) it'll fail, the NON-US Zers have to buy
a replacement Power Transistor Unit , very often at a overinflated price
(depending on your country, you may be charged between 2 to 5 times the
US price).
And to add insult to injury, the power transistor unit you'll then get
will have the same old, faulty design, and will fail again (guess how I
know ?)
The best workaround is to buy one in the US , and install it yourself
(it's easy, and can be done in about 20 minutes)
Henri Le Hir
Pre-cats
Only on TTs. The pre-cats are a second set of catalytic
convertors for cold start emissions purposes. They are immediately
after the turbos in the exhaust pipes. The main cats are sufficient to
pass regular emissions tests, so a lot of the time they are 'gutted' or
replaced with downpipes, gaining ~10rwhp & decreasing spool-up
time, while still meeting most standard emissions requirements.
Dallas DamonZ
Pre-silencers
The stock exhaust & some performance cat-back
systems utilize pre-silencers to aid the mufflers in quietening the exhaust
note. They come between the main cats and the muffler sections of the exhaust.
On other performance exhaust systems, they are replaced with an 'H'
or 'X' style pipe.
Dallas DamonZ
Safety Boost
Slicktop
Production model of the Z possessing a hardtop to the driver's cabin
in lieu of the T-roof or convertible top. Relatively few were produced
and all were normally aspirated. These machines are approximately 200 pounds
lighter than the standard T-roof model.
Kevin (Jacksonville)
Soft Valves (early models)
This is a known problem with the very early '90+ Z's, both NA and TT.
Somewhere around 350 1990 Z motors were produced with 'soft' intake
valves. The chances of having one of these engines is pretty remote.
There were 35,000 or so 1990 models sold in the US alone. It took Nissan
until mid-1992 to get enough data together to determine what the problem
was and to isolate it when it occurred. By then, cars had tens of thousands
of miles on them, so it's not a problem that occured in the early stages
of ownership. Although Nissan published a Technical Bulletin describing
the problem and giving the engine serial numbers affected, not all of the
engines in the group will experience the problem.
Other problems could cause these symptoms including a worn spring in
the intake valve timing cam. This is also a known problem, which Nissan
diagnosed in 1992 also and issued another Technical Bulletin about. This
is much more common and could be the problem here. Three things could cause
the noise: the VTC tensioner spring, the auto tensioner, or a lifter. Nissan
indicates in the Technical Bulletin that the lifter is the primary suspect,
followed by the VTC spring and then the tensioner.
Then, just to confuse things, Maximas, which use a different head, have
a similar problem that's caused by some other things. I mention this because
some folks have confused the Maxima problems with the 300ZX ones because
the engines are similar.
The 'soft' valve problem *could* be in NA engines with serial numbers
lower than 777599, while TT engines are lower than 619550. The engine serial
number is located on the rear of the passenger's side head. Car assembly
dates are earlier than June 22, 1990 for NA's and December 11, 1989 for
TT's. The intake cam problems are NA ENGINES ONLY, and are for engine serial
numbers lower than 475679 in cars with VIN's lower than 012836 for the
coupes and 003754 for 2+2's
Tom Bell(WI)
Spool
Spool up time is the amount of time it takes to reach full boost
from a turbo. Spool up is a function of turbo design
and how much exhaust flow reaches the turbo. On the ZTT, this is at about
3500 rpm's.
Larger aftermarket turbos can have nearly stock spool up, but will flow
more air which produces more power per given boost pressure level(psi).
Chris(Miami)
SR-71
The SR71 is a limited edition 300ZX that was modified by Texas Motorsports
and was done similar to what Saleen does to the Mustang.
They took stock 300ZXs and upgraded them to a Stage
VII w/NOS using mostly HKS products,
along with Kaminari bodykit and forged 3pc BBS rims.
Kyle(Houston)
Stages
This is the standard benchmark Twinturbo Z stage chart. Most people
use this as their performance upgrade path:
| Stages: |
Modifications Required: |
Approximate M-T HP at Flywheel & Boost Pressure |
| Stock |
None |
300hp 9.5 psi |
| Stage I |
Performance cat-back exhaust system |
320hp 10 psi |
| Stage II |
High flow intake |
340hp 10.5 psi |
| Stage III |
ECU EPROM upgrade & boost jets |
396hp 13.5 psi |
| Stage IV |
Larger intercoolers |
405hp 13.5 psi |
| Stage V |
EVC |
418hp 14.5 psi |
| Stage VI |
555cc injectors & 550 type turbo upgrade |
445-500hp 16.5 psi |
| Stage VII |
Dual high flow intake |
520hp 16.5 psi |
| Stage VIII |
600 type turbo upgrade |
620hp variable psi |
| Stage IX |
NOS |
680-760hp variable psi |
This standard stage chart is a bit dated. SGP
Performance has made an updated TT chart to include newer modifications
& rearranged a few of the steps in their performance upgrade path.
On the forum, you'll see this noted as SGP Stage ????.
| Stages: |
Modifications Required: |
Approximate M-T HP at Flywheel & Boost Pressure |
| Stock |
None |
300hp 9.5 psi |
| Stage I |
JWT POP charger & Underdrive pulley |
305-325 hp 10 psi |
| Stage II |
JWT ECU upgrade & boost jets |
365-380 hp 12-14 psi |
| Stage III |
B&B test pipes & Gut pre-cats |
385-400 hp 12-14 psi |
| Stage IV |
Performance cat-back exhaust system |
400-415 hp 12-14 psi |
| Stage V |
EVC |
420-435 hp 15 psi |
| Stage VI |
JWT NOS system |
490-505 hp 15 psi |
| Stage VII |
Larger intercoolers |
495-510 hp 15 psi |
| Stage VIII |
JWT dual POP charger |
510-525 hp 15 psi |
| Stage IX |
Ported throttle bodies & Matched intake |
515-530 hp 15 psi |
| Stage X |
NISMO 555cc injectors |
530-545 hp 17 psi |
| Stage XI |
Sport 500 turbos
Sport 600 turbos
Sport 650 turbos (cam upgrade required) |
555-575 hp 17-21 psi
560-605 hp 17-21 psi
620-675 hp 17-21 psi |
| Stage XII |
JWT cams & SGP head package |
640-695 hp 17-21 psi |
The standard stage chart for NAs:
| Stage: |
Modifications Required: |
Approximate M-T HP at Flywheel |
| Stock |
None |
222hp |
| Stage I |
Performance cat-back exhaust system |
234hp |
| Stage II |
Computer Upgrade & Intake |
254hp |
| Stage III |
Nitrous Oxide & Injector Upgrade |
300-320 hp |
Again, SGP Performance
has created a more up-to-date NA performance upgrade path to follow:
| Stage: |
Modifications Required: |
Approximate M-T HP at Flywheel |
| Stock |
None |
222hp |
| Stage I |
JWT POP charger & Underdrive pulley |
238 hp |
| Stage II |
JWT ECU Upgrade |
250 hp |
| Stage III |
Performance cat-back exhaust system (also ALC for A-T) |
262 hp |
| Stage IV |
Stillen headers |
279 hp |
| Stage V |
Ported throttle bodies & Matched intake |
290 hp |
| Stage VI |
Injector upgrade & JWT NOS system |
390 hp |
| Stage VII |
SGP head package (porting & 5 angle valve job) |
420-430 hp |
Dallas DamonZ
Sway Bar
A sway bar is connected to two points on the suspension, across the
frame, from left to right. Their use results in less body roll and a stiffer
suspension.
Joe VA
Test Pipes
Throttle Bodies
Connects intake piping to intake manifold. Throttle position sensor
and throttle position switch are attached. Contains a butterfly valve -
when the accelerator is pushed down it pulls a cable which is connected
to the thottle body, which causes the valve to open, allowing air to flow
into the engine.
PWS
TPS-Throttle Position Sensor
A sensor connected to the outside of the driver side throttle body
that feeds information back to the ECU telling it where
the throttle position is. The connections on the TPS can often get dirty
and cause an erratic idle. Cleaning the TPS connector can often cure idling
problems.
Steven(Phx)
Turbos
Basically, a turbo is an exhaust-gas driven air pump. Exhaust gases
exit the engine, run through the turbine section of the turbo, spin the
turbine, and then exit the vehicle through the exhaust system. The turbo's
turbine is connected via a shaft to the turbo compressor. The compressor
is spun by the turbine, and compresses intake air to the engine. As the
intake air is compressed it is made more dense. Because the air is more
dense, more air, and therefore more oxygen, flows into the engine on each
intake cycle. The engine's ECU measures the air and
adds the correct amount of fuel. Therefore, compared to a normally-aspirated
(NA) engine, more oxygen goes into the engine and more power is made.
The intercoolers come into play by reducing
the temperature of the intake air after being compressed by the turbo,
further increasing intake air density.
Turbo wastegates allow some exhaust to pass around the turbo's turbine
under certain conditions (i.e., to avoid over-boosting the engine).
The shaft connecting the turbine and compressor is supported by an oil-lubricated
bearing. This bearing cavity is cooled using engine coolant. When people
talk about letting a turbocharged engine idle for a bit after start-up
and prior to shutdown, it's due to this bearing.
njttz
Turbo Timer
A Turbo Timer is an electronic device that will allow your engine to
keep running AFTER the ignition key was turned OFF and removed, either
for a preset amount of time (most of them), or a computed amount of time
(based on how "hard" you drove)
Some of them have additional functions (like a boost
gauge) They may require electrical skills to install them if the car is
fitted with an auto-activating alarm, or if they aren't provided with a
wiring harness for installation
They will prevent the common mistake to simply shut down a turbo engine
after a "hot" run. If the engine is directly shut down, oil will stop flowing,
may "cook" in the turbos and this may damage the turbo's
bearings.
It's a "nice to have" gizmo, but not absolutely necessary if...
- You let your engine idle down from 30 secs to 2 mins before shutting
it down
OR
- You do NOT engage the boost for the last 2 minutes of driving before
stopping the engine
- Use of 100% synthetic oil will greatly reduce the risk of "cooking"
your oil (but you'll still have to let the car idle)
Henri Le Hir
Underdrive Pulley
An underdrive pulley is a pulley that is smaller in diameter than the
pulley it replaces. The diameter of the crank pulley is reduced a specific
amount (from 20-30%), depending on the vehicles accessory needs. In other
words, all accessory minimums are retained: air conditioning efficiency,
power steering feel, and voltage (minimum allowable voltage 12v), even
at idle, with everything on in the car. With the smaller diameter of the
pulley the car will rev up quicker. Weight loss is the most critical
factor in HP production, each lb. of mass taken off the crank/eccentric
shaft is worth approximately 2.7 HP and the figure increases with forced
induction and as RPM's increase.
Kyle(Houston)
Valence
Basically the rear bumper & ground effects, some aftermarket body
kit suppliers have bumper replacements or a bumper 'cap' that covers the
bumper area & adds different ground effects.
Dallas DamonZ
Welding Tips
X-Pipe
A new style of exhaust pipe between the main cats
& the mufflers sections. The left & right side pipes actually come
together in an 'X' fashion for better exhaust pulse blending.
Dallas DamonZ
Z32
Nissan's model designation for the '90+ 300ZX. The '84-'89 300ZX is the Z31.
Dallas DamonZ
|
