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Engine / Fuel / Intake

Upgrades & Modifications

Intakes / POP Chargers / CAIs
Installing an SR20DET
JWT Cams
JWT Cams & Timing Chain Install Pics
Magnecor Ignition Wires
Polishing the Valve Cover
Power Steering Fluid Cooler Installation
Remote Oil Filter
Stillen Fuel Pressure Riser
The Wayne Cox HP Trick
Unorthodox Racing Pulleys
Unorthodox Racing Pulleys Stage 2

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Engine Performance Tuning Tips
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes) Timing
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Synthetic Oils and Lubricants
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Air Intakes
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  ECUs
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Cam Shafts
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Adjustable Cam Sprockets
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Headwork
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Pistons
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Crank, Rods, Bearings, Machining,
bullet_blank.gif (76 bytes)Balancing, Coatings, Manifolds, etc.
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Extrude Honing

bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Unorthodox Racing Underdrive Pulleys
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Spark plugs and Ignition systems
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Big Bore Throttle Bodies and MAFs
bullet_blank.gif (76 bytes)bullet_blue.gif (891 bytes)  Reader's Contributions
Changing Belts
Changing the Fuel Filter
Changing the Fuel Injectors
Changing the Oil
Cleaning the Throttle Body
Cold Idle Fix
Idle Speed Adjustment
MAF Sensor Grounding
Motor Mount Extravaganza (by John Heer)
Motor Mounts (comments & pics)
Replacing Motor Mounts
Replacing the Oil Pressure Switch
Replacing the Power Steering Fluid
Replacing the Timing Chain Tensioner
Replacing the Water-Pump
Synthetic or Dino Oil?
Tuneup and Troubleshooting Guide
About Ignition Timing
About Airflow sensors
About Idle Air Control Valves
Bosch Platinum vs. NGK Platinum Spark Plugs
Bowling's Automotive Programs
Break-In FAQ
ECU Trouble Codes
Engine Block Preparation Guidelines
Engine Oil Bible
Fuel Injectors
Gasoline FAQ
How to make your own AFR Meter
Missing Oil Syndrome
More info on Oil
More info on Fuel
Oil Filter Analysis
Platinum vs. Copper NGK spark plugs
Snake Oil Info
Some interesting info on Slick-50
Spark Plugs and Ignition Systems
Specialty Spark Plugs
The Limit of Bolt-Ons
TPS Voltage Adjustment
Torque vs. HP
Info on Other SR Engines Nissan Engine Designations

Open Loop vs. Closed Loop

red_triangle.gif (202 bytes) Comments by Dan Thompson

In automotive terms, "closed loop" refers to the mode of operation whereby the ECU monitors input from all sensors and trims fuel delivery and timing maps to optimize engine performance. During "open loop" operation, all but a few critical sensors (TPS, MAF, coolant temp and Crankshaft Position Sensor on our cars) are ignored, and fuel delivery and timing are based on pre-programmed maps.

High port versus low port

red_triangle.gif (202 bytes) Comments by Dan Thompson

To set the record straight, 'high port' or 'low port' describes the intake manifold's entry point into the cylinder head. If the cylinder head's intake ports are located toward the top of the head, it is considered a high port head. If the ports are located toward the bottom, it is a low port head.

The high port head was in all NX2000s as well as the '91 thru '93 Sentra SE-R. The switch to the low port head on U.S. Nissan models (I'm not sure about Infinitis) occurred in 1994. All SR20DE engines installed in Nissans from 1994 to present have been the low port model.

If you're *still* not sure whether you have a high port or low port head, look between the valve cover and the firewall. If you see an object that looks kind of like a log (which is the surge tank), you have a low port head. If you see 4 "tubes", you have a high port head.

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