2007 GX470/2UZ-FE Engine Rebuild

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rancejunge

Rank I

Contributor III

124
Joplin, MO, USA
First Name
Rance
Last Name
Junge
These pistons were designed for another engine 94mm bore that ran 10.2 to 1 compression and 18 psi boost from twin turbos. 24mm wrist pin 31.5 compression ht. 51mm Total ht. rings included. They have steel reinforced ring/piston land support to handle that kind of pressure with durability. Factory 2uzfe pistons have 33.9 compression ht with 70% -6.8mm dish out in the center and 22mm wrist pin. Will take some cc and maching work which should be pretty easy.
 
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Zander Abear

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Zander thanks for sharing all of this and great info! You should have put forged pistons with ductile iron rings in it with a slight more compression if you are thinging about boosting. I am in the process of building this now for my GX470. I am using the same rods in mine also. What did it cost you to bore the engine?
If I remember correctly cleaning up the entire block was around $1,400. It was a bit more then I planned for initially. I started with a block that had been sitting for a while outside, Unprotected from the elements. Had an overbore, head surface decking on block and heads, they ordered my pistons, balanced my rotating assembly, and finally had a couple holes re-drilled and helacoiled. I believe it was more expensive mostly because the machine shop I went to doesn’t exactly see a lot of Toyota V8’s. In fact, they stated they have never worked on a 2UZ, or any Toyota V8 ever. I was planning on getting some forged pistons when I started this project, but when I found out I could get OEM pistons for $65 a pop, it sounded a lot better then $2000 for 8 of them. Besides, I haven’t seen any major issues with the stock pistons. Even if I boost it down the road, it won’t be 30psi or anything, probably closer to 7-10. Sadly, I’m still working on putting the motor back in. Motor is fully assembled and has been for a while now. I just don’t have much room in my garage because we just emptied out my parents lake house. With it getting cold in Chicago, and not even getting home from school 30 minutes before the sun goes down, I haven’t had good time to get some work in. I swear the world is working against me. I will get this engine in! Even if it’s the last thing I do!
 
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rancejunge

Rank I

Contributor III

124
Joplin, MO, USA
First Name
Rance
Last Name
Junge
Well I got my long block together now with the LF4 pistons in. Ther were no clearance issues but it will be an interference engine. Even after polishing the combustion chamber to a mirror finish and un shrouding the valves it is making 11:1 compression with a cold engine compression test pressure of 210 to 220 psi. Hope I can manage 6 psi boost with the TRD supercharger without detonation issues . Right now I am adding a water to air intercooler to the TRD supercharger which is a lot of machine work. The heads ported nicely but 32 valves took me a while LOL! I am trying to see how big of injectors I need to go with for the power this will produce. My Audi RS6 with a Biturbo 4.2 liter V8 uses 78 lb injectors. What I am really trying to make is a high torque low rpm engine that will be more fuel efficient so I want the high compression ratio and low friction these coated pistons provided.IMG_20230403_185402433.jpgIMG_20230402_190750370.jpgIMG_20230402_190944780.jpgIMG_20230402_191128327.jpg
 
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