C6Performance Journal

• All Gen III truck engines use iron blocks. Only the Camaro (F-car) and Corvette (Y-car) LS1/LS6 engines feature aluminum blocks.

• All Gen III engines have aluminum heads except for the ’99 LQ4 engines that were equipped with iron heads. These engines received aluminum heads for the 2000 model year.

• All Gen III engines share common main, rod, and cam-bearing journal diameters for ease of interchange. All blocks use a cross-bolted six-bolt main cap.

• All Gen III engines are completely metric.

• All valvetrain pieces are completely interchangeable. The standard rocker ratio for all Gen III engines is 1.7:1.

• All Gen III truck engines use cast- aluminum oil pans that are deeper than either the Camaro or Corvette pans.

• All intake manifolds interchange. The truck intakes are roughly 3-4 inches taller than the passenger-car intakes.

• All Gen III engines employ reusable gaskets for all sealing surfaces except for the head gaskets. This makes it much quicker and easier to service the engine.

• There are only two intake valve sizes for all the Gen III engines. Exhaust valves are all the same diameter.

• Truck and Camaro engines use cable throttle linkage while the Corvette uses an electronic throttle. There are also some SUV engines with traction control that use an electronic throttle control.

• Bellhousing patterns are the same for all Gen III engines. The crank flange is basically the same depth as the bellhousing flange.

• The Gen III firing order has been revised from 1-8-4-3-6-5-7-2 to 1-8-7-2-6-5-4-3. Note that the pairings 1-8, 4-3, 6-5, and 7-2 remain the same, but the pairing order is different for reduced vibration.

• The valve angle on all Gen III engines is 15 degrees versus 23 degrees for the original and Gen II small-blocks.

• The Gen III bore spacing is the same as the original small-block, but each cylinder is ringed with only four head bolts instead of five.

taken from Chevy High Performance.

SS Performance Package – includes 325-hp 5.7L LS1 V8 with forced air induction system, unique hood air intake, low restriction exhaust system, synthetic engine oil, P275/40ZR17 Goodyear Eagle F1 performance tires (maximum speed rating), 17″ x 9″ 5-spoke aluminum wheels, specially-tuned performance suspension with larger front stabilizer bar, stiffer springs, unique shock valving and stiffer bushings, specific exterior and interior “SS” badging and unique rear deck-lid spoiler

Ram Air Performance and Handling Package – includes specific low restriction dual exhaust system, Ram Air induction system, functional hood scoops, 325 hp, 5.7L LS1 V8, P275/40ZR17 performance tires (maximum speed rating), 17″ high-polished aluminum wheels, specific front and rear suspension with higher front and rear spring rates, unique shock valving, stiffer Panhard bushings and 3.23:1 rear axle ratio with automatic transmission; includes 3.42:1 rear axle with 6-speed manual transmission

The 1998-1999 and some 2000 WS6’s got 1LE springs and other minor 1le parts, different decarbon shocks, ect. Nothing major, but it was more than the simple swaybar upgrades of the mid 2000-2002 cars got.

1998’s also did not get the dual exhaust, instead they got a 3.5″ stainless 1 out the left

**** Just because an ls1 is equiped with the optional “performance” packages does not make them faster ****

• Torque Convertors: How they Work– What size is right for you? depends on the application DO YOUR OWN RESEARCH, start in the Automatic Transmission Forum we have here, its there for a reason . General rule is 3200-3600 for daily drive, 4k+ for alot of track use.

• Manual Transmissions: How they Work– When looking to upgrade think of current and future mods. 01-02 cars come with the ls6 clutch and hydraulics which is a good setup for basic bolt on and daily driving.

  – You’ll find the Spec 3 to be one of the most popular clutch setups here. Ram also makes a nice setup. Again, Do your OWN research n he Manua Transmission forum concerning chatter, clutch break in, hydraulics, ect. 98-00 cars will want to upgrade to the 01+ hydraulics when installing a new clutch.