For anyone thinking about one of these great little V8's for their project, here are some useful facts about them:
The aluminum block motors are the 4.0l 1UZ-FE and 4.3l 3UZ-FE, and are found only in the Lexus line. The aluminum motors weigh around 420 lbs, fully dressed with all accessories
The cast iron block 4.7l 2UZ-FE is found in Toyota's 4-Runners and Tundras, and it weighs around 500-510 lbs, dressed.
All motors will fit in a 650-720mm cube, making them one of the most compact OHC V8's in the market, and comparing favorably with the smaller OHV cam in block V8's.
All are DOHC, 32 valve motors with aluminum heads, and the aluminum block motors have six bolt mains, while the iron block 2UZ has 2 bolt mains.
All rods in all motors are powder forgings, but the pre-95 1UZ rods are stronger than all the rest, with beefier cross sections. The weakest rods are found in the 2UZ motor. All rods are interchangeable between motors.
Toyota's technical documentation states that the 1UZ and 3UZ motors have forged steel cranks, while the same docs state only that the 2UZ motor's crank is steel (no mention of forging).
The later (post '98) 1UZ engines have heads which flow better than the early 1UZ heads, however the later heads also have a variable valve timing system.
The pre-'98 aluminum motors used a dual distributor ignition system, which can be converted to crank trigger fairly easily. The post '98 motors eliminated the distributors and were fully crank/cam triggered with a COP setup. The COP setup from the later motors is not a direct fit onto the early motors as the heads are slightly different. The firing order for all motors is: 18436572 (same as Chevy).
The 98 and later motors use a variable timing system on the intake cams which Toyota calls VVTi. This system makes the later motors less desirable to hotrod as few standalone ECU's on the market have the capability to control this system properly.
Rear sump motors come from the Lexus SC400, mid-sump from the GS400, and front sumps from the LS400. The sump position probably is of little concern for a midengine project, but can be a showstopper for swapping these motors into other cars.
Tranny adaptors, ITB setups, supercharger kits, hot cams and valve trains, forged pistons & rods, etc. are all available in the aftermarket. Nearly all the go fast parts are designed for use with the earlier (pre-VVTi) engines. The Aussies have been hotrodding these motors for years, while in the US they're "just" being discovered, which is why they're still so cheap on eBay. Typical prices range from $250 to $750 USD for these motors.
And
www.Lextreme.com certainly has loads more information about these motors (shameless plug for a great website
).
Here's a pic of one of the more "lextreme" examples:
This "mule" motor was plucked from a salvage yard, and according to its owner/builder, they're "running it to 7400, and apart fron intake, exhaust and dry sump, engine is still standard." It's being tested in this Reynard chassis, with the intent of competing in the Australian OZ-Boss series:
