Lexus Piston Rods (1uzfe, 2uzfe, 3uzfe)

UPDATED LEXTREME FORUMS - Post Questions Here!

Lexus is known for its reliability and smoothness of the powertrain.  The heart of the 1UZFE is the block and the other moving parts also play a very important role to work as a world class engineering.  I have cut up a 1UZFE piston and exam the internal materials and measurements.

One of the reasons why Lexus engine are so smooth and quite is because the pistons are balanced to zero.  With proper tuning and controlling the heat factor, the stock internal (decompressed) can easily handle 850 bhp.

However, if you desire more horse power, you will need racing pistons.  The below information can be use as a guideline for custom aftermarket forged pistons.

The 1UZFE had demonstrated to have an average life of 400,000 miles.  However, some 1UZFE had reached 600,000 miles.  However, for forced induction, aging motor needs rebuild and refresh.  Natural Aspirated engine is different from forced induction engine.  If your engine have more than 130,000 miles and you plan to run forced induction.  You should rebuild your motor first with after market forged dished pistons.  The crank and rods are pretty strong.  Here is my recommendation for mild rebuild:

  1. Forged dish pistons
  2. Multi-Layer Steel (MLS) Gaskets
  3. ARP Racing head studs

The above combo is mild modifications and should able to handle around 900 to 1100 bhp.   Still need more?  Stronger rods will be required.  The factory pistons are forged with 3 rings.  The first two is for compression and the last ring is for the oil.  After a closer examination of the rods.  The are cast steel with special coating.  Once again, the rods are not forged as stated by others.  Here are a factory specifications on the rod and piston.

 

 

 
This is a overview of the 1UZFE rod along with end cap and screw
 
 

 
Here is a closer look at the end cap and screw. The screws are hex. shape.
 
 

 
Bottom view of the end cap and hex. screws.
 
 

 
More view of the hex screw
 
 

 
This is the end cap unassembled with two openings for screws and two other openings for rod guide.
 
 

 
Here is a side by side rod and end cap. Noticed the rod has the male and end cap has the female.
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
 

CONNECTING RODS SPECIFICATIONS
CONNECTING RODS TABLE
Application	In. (m m)
Bore Diameter		
	Piston Pin Bushing		.8663-.8668 (22.005-22.017)
	Big End (Crankpin)	
   	Reference Mark "1" 		2.1654-2.1656 (55.000-55.006)
	Reference Mark "2"		2.1656-2.1658 (55.006-55.012)
	Reference Mark "3"		2.1658-2.1661(55.012-55.018)
   	Reference Mark "4" 		2.1661-2.1663 (55.018-55.024)
Maximum Bend (1) 			.020 (.050) 
Maximum Twist (1) 			.0059 (.150) 
Side Play
	New or Rebuilt 	 (2) .0059-.0130 (.150-.330) 
	New or Rebuilt 	 (3) .0063-.0130 (.150-.330) 
	Service Limit 	 (2) .0150 (380) 
	Service Limit 	 (3) .0138 (380)
Rod Bolt Shank Diameter
   	New or Rebuilt 	 .2835-.2874 (7.200-7.300) 
   	Service Limit 	 .2756 (7.000)
	(1) - Per 3.94" (100 mm) of connecting rod center-to-center length.
	(2) - 1990 Model. (3) - 1991 Model.
PISTONS, PINS & RINGS SPECIFICATIONS
 PISTONS, PINS & RINGS TABLE
Application	In. (m m)
Pistons
Piston-to-Bore Clearance
   	New or Rebuilt 	 .0008-.0016 (0.20-0.40) 
   	Service Limit 	 .0024 (.060) 
Diameter
	Size Mark "1" 	 3.4437-3.4441 (87.470-87.480)
	Size Mark "2" 	 3.4441-3.4445 (87.480-87.490) 
	Size Mark "3" 	 3.4445-3.4449 (87.490-87.500)
Piston Pin
	Diameter		.8860--.8665 (21.997-22.009)
	Piston Fit 	 (1 ) )
	Rod Fit 	 (2 ) )
	New Or Rebuilt 	 (3 ) .0002--.0004 (.005-011)
 	Service Limit 	 (3) .002 (.05))

Rings 
	No. 1
	End Gap
	New or Rebuilt  	.0098-.0177 (.250-.450) 
	Service Limit	.0413 (1.050)
	Side Clearance	.0008-.0024 (.020-.060)

	No. 2	
	End Gap	
	New or Rebuilt 	.0138-.0244 (.350-.620)
	Service Limit 	.0472 (1.200)
	Side Clearance 	.0006-.0022(.015-.055)
	
	No. 3 (Oil)		
	End Gap (Side Rails Only)		
	New or Rebuilt 	.0059-.0224(.150-.570)
	Service Limit 	.0433 (1.100)
	(1) - Push fit @ 140∞ F (60∞ C) (2) - Push fit.
Here is a more accurate measurement by using a professional caliper. 

Crank side diameter without bearing is: 2.155" 
Piston side pin diameter: .857" 
Rod length is: 4.238" 
Center to center would be 2.155"/2 + .857"/2 + 4.238" = 5.744" 
Crank side thickness: .900" 
Piston side thickness: .826" 

There has been talks in our forum that Honda H22 rods and pistons might work in our 1UZFE engine. The area is being explore as we speak.   
Hopefully we can use some of the after market racing parts. 
Do you have any questions? If so, please head over to the forums to get a quick answer or share your experience!

This is a freelance site with no support by huge companies.  I have been doing most of the R&D and technical write-ups by myself with my personal money and literally thousands of hours of my time.  I have taken extra steps to demonstrate in details how things are done.  Currently I am one of the few people doing Lexus V8 research and performance enhancement.  This effort comes from my personal love for this wonderful engine.  Most of the modifications are from trill and errors.  There is no cookbook for the 1UZFE modifications and its a virgin territory for performance.  The parts, labor, web development and site hosting are from my personal hobby money.  If you feel my efforts help you in any form, please do not hesitate to donate any amount of money to support this site. You have no idea how much I appreciate it!

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