32-bit Windows allocates only 2 GB of virtual space per one application. Also that block of 2 GB can be fragmented (for example, by some DLL file), there are no such limitations in 64-bit Windows.

Source: http://www.carbonetic.net/faq/

• Are the Carbonetic LSD’s noisy and/or chattering in operation?
• Not at all, our LSD’s are almost OEM quiet and smoothly working.
• Do the LSD’s need to be bedded in?
• Yes it does, we recommend you do about 180 miles and then change the LSD oil to remove any of the carbon deposits. Our technical section informs you about the bedding in.
• What oil do I have to use, can I use normal LSD oil?
• No we do not recommend standard gear oil with the Carbon LSD, we suggestion using the Carbonetic Oil available from your local dealer. But if you cannot get hold of the Carbonetic oil, we have tested other brands that work with the Carbon LSD:

For FF/AWD application
MOTUL	Gear Competition SAE75-140
NEO Synthetic oil	75W90RHD
For FR application
MOTUL	Gear Competition SAE75-140
MOTUL	90PA
NEO Synthetic oil	75W90RHD

• Are the LSD’s re-buildable?
• Yes they are, we hold full stock of every part need to rebuild and service the LSD.
• Can you tell me more about 1 way, 1.5 way and 2 way LSD’s?
• The Blade can hold a maximum of 400 WHP and400 Ft-lb torque at wheel.



• 1 way lsd: An LSD is activated only when the throttle is on and when the internal cam rings has an angle on only one side.1.5 way lsd: The angle of the cam rings for the off-side is very close to 5-20 degrees which will make the LSD ineffective when the throttle is off (during deceleration).The Across 1.5-Way LSD will work similar to 1-Way LSD during deceleration.
• 2 way LSD: The 2-Way cam rings angle are cut in the same degree on both sides (throttle on and throttle off sides). A 2-Way LSD will activate during both acceleration and deceleration. 2 way is a popular choice for drifting.

Source: http://www.exhaustvideos.com/faq/how-to-calculate-muffler-size-pipe-diameter/

How To Calculate Muffler Size and Exhaust Pipe Diameter

If you’re a math wiz and/or an engineer, you’re probably going to like this article and the resources we’ve linked to. However, if you find yourself getting stuck (or bored) with the info below, here are the key take-aways:

1. The factory exhaust pipe diameter is usually a good choice for most vehicles.

2. The muffler manufacturers are doing all the math for us – no need to reinvent the wheel. If they say it will work for your vehicle, it will probably work for your vehicle.

3. We’ve got an easy-to-read exhaust system size table that is good for quick calculations.

Breaking Down The Problem

While we’re not going to go through and list out all the formulas and calculations you need to figure this exactly, we will break down the problem, explain how you would go about figuring things out scientifically, and then leave you with some good quick-and-dirty exhaust system math as well as some interesting links.

The science goes like this…

1) Mass of air that the engine breathes in + mass of fuel = mass of exhaust gases

Conservation of mass, right?

2) To calculate the volume of air the engine takes in, we multiply the displacement of the engine by the engine RPM and then divide by two (it takes two full revolutions for the engine to exhaust it’s entire air volume). We then convert that to volume to mass.

3) To make the calculations easy, you want to assume that combustion is perfect, i.e. there aren’t any byproducts, any unburned fuel, etc. It’s easier to assume perfect combustion and then “back in” to the actual numbers using an estimate after the fact.

4) Since you’re assuming perfect combustion, it’s easy to figure out how much fuel mass is added to the exhaust.

5) Once you know the mass of the exhaust gas, you just figure out how much volume that mass would occupy. Of course, you have to adjust for expansion due to the high exhaust gas temperature.

That’s it! Of course, when you sit down to figure it, you’ll find that getting a good scientific estimate takes a lot of work (which is why we don’t bother with it here).

Quick and Dirty Exhaust System Math

Easy Way To Estimate: Your intake system needs to flow 1.5 CFM per engine horsepower, and your exhaust system needs to flow 2.2 CFM per engine horsepower.

Good Way To Estimate: Take engine RPM x engine displacement, then divide by two. This is the intake volume. Use this same volume of air for the exhaust system, but then correct for thermal expansion (you need to know exhaust temps to figure things out).

Exhaust Pipe Size Estimate: A good section of straight pipe will flow about 115 CFM per square inch of area. Here’s a quick table that shows how many CFM each common pipe size will flow, as well as the estimated max horsepower for each pipe size:

NOTE: These numbers are just estimates. All pipes are assumed to be 16 gauge steel.

The table above is probably over-estimating pipe size, but you can see that a 400 hp vehicle with a dual exhaust system only needs 2 1/4 – 2 1/2 inch pipes. Anything larger is overkill.

Source: http://www.exhaustvideos.com/faq/how-to-calculate-muffler-size-pipe-diameter/

Useful link:

http://www.bgsoflex.com/displacement.html
http://www.4secondsflat.com/Carb_CFM_Calculator.html
http://www.superchevy.com/technical/engines_drivetrain/exhaust/0505phr_exh/index.html
http://www.nsxprime.com/FAQ/Miscellaneous/exhausttheory.htm
http://www.physicsforums.com/showthread.php?t=267530

Basic Injector Information

Introduction

For the purpose of simplicity we will only deal with injectors that have applications for the 350Z with the VQ35DE.

The stock VQ 35DE comes with injectors from various manufacturers. The injector brands are installed at the factory randomly. What ever the factory had in stock is what your car received. You may notice that your stock injectors are a different color than your friends. Regardless of color or manufacturer they are the same size and performance. They are all high impedance injectors flowing 320CC per min @ the stock 52psi of fuel pressure or 3.5bar.

Injector Impedence

Injectors are classified as high impedance or low impedance depending on their electrical resistance. High impedance injectors have a minimum electrical resistance of 8 ohms or more with a typical resistance of 12 ohms. They are called saturation type injectors and use simply constructed saturated driver circuits. Low impedence injectors are less than 3 ohms the most typical being 2 ohms. Low impedance injectors use peak/hold circuits. Their flow is more precise and the injectors and control circuits are more expensive to manufacture.

Low impedance injectors respond faster to signals from the ECU giving the car better idle characteristics. During high performance use the high impedance saturation control injectors get hot and can fail because of the heat generated by the continuos current. Low impedance injectors use reduced power and run cooler. With low impedance injectors the spring that closes the internal valve shutting off fuel can be stronger resulting in faster closing times and more precise metering. A low impedance peak/hold injector sends a 3 ohm signal to open the injector and then holds the injector open with a 1 ohm signal greatly reducing heat.

Most aftermarket injectors we deal with concerning the VQ35DE are high impedance saturation injectors because of the ease of the direct swap for the OE injectors. The bigger the high impedence injectors you go with generally the worse your idle will be due to the above mentioned nature of the saturation injector having less control at idle. The bigger you go the worse the control.

HKS has several sizes to choose from in low impedance injectors for use with their FCON V-Pro and the Haltech PnP standalone. Low impedance injectors will not work with the UTEC.

Fuel Injector Flow Rating

The industry standard for rating the flow of an injector is 3 bar of pressure or 3 atmospheres which equals 44psi. The APS injectors are flow rated @ 3bar while the other popular injector Deatschwerks are rated @ 3.5 bar because as previously mentioned the Z runs a base fuel pressure of about 52psi or 3.5 bar. A 550 Deatschwerks injector will only flow approx 500 cc per min when being rated at the industry standard of 3 bar. Deatschwerks has since changed their rating method and are now offering injectors rated @ the 3 bar standard. The injectors they sell now are 380, 440, 600, and 850 with custom flow rates available so they can now be directly compared to the flow rates of the RC, APS, PE and HKS injectors. All the new Deatschwerks injectors now come with new Denso cores instead of used cores they received back from customers.

How To Choose Injector Size For Your Application

At 52psi of pressure on a turbocharged motor the injector flow rating should be what you can expect to make in terms of rear wheel horsepower with that injector @ 85% duty cycle. So if the injector is a Deatschwerks 600 rated at 3 bar then you can expect to make 600whp @ 52psi of fuel pressure @ 85% duty cycle. For longevity of the injector 85% of the injector duty cycle should not be exceeded. The exception to this above rule is supercharged applications. Expect to need about 20% more injector for your given whp than a turbocharged application would use. These power levels are based on a constant fuel pressure across the RPM band which may necessitate upgrading to a return type fuel system.

Top Feed Or Side Feed

The VQ35DE uses top feed injectors.

So Which Are The More Popular Injector

As far as ease of use the Deatschwerks are direct drop ins. The RC injectors used to require soldering pigtail connectors into the factory wiring harness, but now come with a patch harness making them plug and play as well. As far as reliability both injectors are good, but there have been more issues concerning the RC injectors than the Deatschwerks. I have never heard of a Deatschwerks injector having issues. I have heard of a few concerning the RC injectors. But RC does stand behind their product and puts an effort forth to make things right. Deatschwerks injectors are a little less expensive than the RC’s. It is very easy to get technical assistance from Deatschwerks by calling their number and talking directly with someone from tech support.

Cleaning and Servicing

Both Deatschwerks and RC offer cleaning and flow bench testing of injectors. Porsche Club of America promotes Chevron Techron concentrate as being a safe and effective fuel injector, valve, and combustion chamber cleaner when used as directed on the label. From tests I have reviewed other in tank injector cleaners proved to do little if anything and are usually a waste of your money.

 

Source: http://m.my350z.com/forum/showthread.php?t=331868

Some say that "an engine needs backpressure to work correctly." Is this true?

No. It would be more correct to say, "a perfectly stock engine that cannot adjust its fuel delivery needs backpressure to work correctly." This idea is a myth. As with all myths, however, there is a hint of fact with this one. Particularly, some people equate backpressure with torque, and others fear that too little backpressure will lead to valve burning.

The first reason why people say "backpressure is good" is because they believe that increased backpressure by itself will increase torque, particularly with a stock exhaust manifold. Granted, some stock manifolds act somewhat like performance headers at low RPM, but these manifolds will exhibit poor performance at higher RPM. This, however does not automatically lead to the conclusion that backpressure produces more torque. The increase in torque is not due to backpressure, but to the effects of changes in fuel/air mixture, which will be described in more detail below.

The other reason why people say "backpressure is good" is because they hear that cars (or motorcycles) that have had performance exhaust work done to them would then go on to burn exhaust valves. Now, it is true that such valve burning has occurred as a result of the exhaust mods, but it isn't due merely to a lack of backpressure.

The internal combustion engine is a complex, dynamic collection of different systems working together to convert the stored power in gasoline into mechanical energy to push a car down the road. Anytime one of these systems are modified, that mod will also indirectly affect the other systems, as well.

Now, valve burning occurs as a result of a very lean-burning engine. In order to achieve a theoretical optimal combustion, an engine needs 14.7 parts of oxygen by mass to 1 part of gasoline (again, by mass). This is referred to as a stochiometric (chemically correct) mixture, and is commonly referred to as a 14.7:1 mix. If an engine burns with less oxygen present (13:1, 12:1, etc...), it is said to run rich. Conversely, if the engine runs with more oxygen present (16:1, 17:1, etc...), it is said to run lean. Today's engines are designed to run at 14.7:1 for normally cruising, with rich mixtures on acceleration or warm-up, and lean mixtures while decelerating.

Getting back to the discussion, the reason that exhaust valves burn is because the engine is burning lean. Normal engines will tolerate lean burning for a little bit, but not for sustained periods of time. The reason why the engine is burning lean to begin with is that the reduction in backpressure is causing more air to be drawn into the combustion chamber than before. Earlier cars (and motorcycles) with carburetion often could not adjust because of the way that backpressure caused air to flow backwards through the carburetor after the air already got loaded down with fuel, and caused the air to receive a second load of fuel. While a bad design, it was nonetheless used in a lot of vehicles. Once these vehicles received performance mods that reduced backpressure, they no longer had that double-loading effect, and then tended to burn valves because of the resulting over-lean condition. This, incidentally, also provides a basis for the "torque increase" seen if backpressure is maintained. As the fuel/air mixture becomes leaner, the resultant combustion will produce progressively less and less of the force needed to produce torque.

Modern BMWs don't have to worry about the effects described above, because the DME (car's computer) that controls the engine will detect that the engine is burning leaner than before, and will adjust fuel injection to compensate. So, in effect, reducing backpressure really does two good things: The engine can use work otherwise spent pushing exhaust gas out the tailpipe to propel the car forward, and the engine breathes better. Of course, the DME's ability to adjust fuel injection is limited by the physical parameters of the injection system (such as injector maximum flow rate and fuel system pressure), but with exhaust backpressure reduction, these limits won't be reached.

- Adapted from Thomas V.

source: http://www.uucmotorwerks.com/html_product/sue462/backpressuretorquemyth.htm

Fail to defence my previous lap time, this time achive 2:37, 4 sec slower than my fastest lap CTA time attach. Got place No 4 in my category. 1 sec slower than Place number 3. Will revenge on next megalap time attack April 21, 2012.

As estimated, round 1 was running in wet I did it with official time 3:00.434, p1 in that session. However, with lack of stamina I not doing in round 2 with the dry track a 4pm.

The event condition was terrible because no pits was allocated to all participants, under the suddent hot suddent wet condition, everyone is torturing by the event.

CC Kang, first time entering time attack, after hefty effort in pushing him into the entry; did pretty well in street tire category, with his under power stock FD2R, he did 2:46. I was doing setup for his car in the morning trackday, handling was perfect but facing too serious under power in gear 3 for sharp corner exit. I would recommend him to change higher camshaft, bigger throttle body and bigget plenum for improve another 20 more horse power.

Fail to defence my previous lap time, this time achive 2:37, 4 sec slower than my fastest lap CTA time attach. Got place No 4 in my category. 1 sec slower than Place number 3. Will revenge on next megalap time attack April 21, 2012.

The rule of thumb is for every 10° Fahrenheit (5.5 Celsius) change in air temperature, your tire's inflation pressure will change by about 1 psi (up with higher temperatures and down with lower).

Source: http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=3

The first photograph shows a tire properly inflated to 35 psi sitting still in the water on the glass plate. This provides an accurate idea of the tire's footprint size and shape. The black area is where the tire's rubber compound is pressed on the glass, and the green areas identify water in the tire's circumferential and high-angle lateral grooves, and on the remainder of the glass plate.

A properly inflated tire will have enough pressure in the center of its tread to resist collapsing. The next picture is of a tire properly inflated to 35 psi, driving across the glass at 60 miles per hour. If the glass plate were dry, the footprint size would be virtually identical to the first picture because air does not prevent the tread from contacting the plate. However with standing water on the plate, the tire's tread depth and tread design must evacuate the water as the tire rolls across the plate at 88 feet per second. You will notice that the footprint still shows good contact with the plate, but is slightly smaller than the static tire's footprint.

A tire that is slightly underinflated will apply less pressure to the center of the tread and it will become slightly concave. The next picture is of a tire inflated to only 30 psi, again driving across the glass at 60 miles per hour. With the same amount of standing water on the plate, the center of the tire's tread is lifted as the tread design unsuccessfully attempts to evacuate water as the tire rolls across the plate. You will notice that the actual footprint shows poor contact with the plate and is significantly smaller than the footprint in the photograph of the properly inflated tire. A tire that is significantly underinflated will allow the center of the tread to collapse and become very concave, trapping water rather than flowing it through the tread design.

The final picture is of a tire inflated to only 25 psi, driving across the glass plate at 60 miles per hour. With the same amount of standing water, the water lifts the center of the tire's tread as its footprint rolls across the plate. You will notice that the actual footprint shows little contact with the plate and has been virtually reduced to the shoulder areas.

Example: Stock 911, 3,000 lb.
(3000/100) = 30 psi
Add 2 psi all around = 32 psi
Add 2 psi to heavy end = 34 psi at rear
With modified suspension, the result is 30 psi front, 32 psi rear.