This is the part 3 of this 1UZ Vs. 3UZ write up. The
examination of the two engines was very interesting and
lextremely enriching. I learn a lot from this experiment.
I think this engine comparison articles break down many
mysteries we had about the legendary 1UZFE and the improved
version of the original. I did not weight the two blocks,
but I would say they must be very close. I do not think
weight is a factor between the two blocks. The picture
below is late model GS430 block. From the look of it, its
very clean and minimum wear if any.
Here is closer look at the 3UZ all aluminum block. You will
noticed this block is very clean.
Something is very interesting I found out when I take out my
measurement caliper. The blocks are identically the same.
However, you will noticed the sleeves size are different.
The Inter-Sleeve Space (ISS) is what I call it. This is
the space between to sleeves. In the 3UZ the Inter-Sleeve
Space is .574" and the sleeve thickness is .187"
Here is my dead 1UZ block I have at home. Even its dead
block I still keep it around for mock fit parts and something
like this. Comparing engine blocks. This block lived
in my carport and get rain on and my lawn sprinkler system.
Therefore, you will see lots of rust and cosmetically
Even its beat up and its ugly, but it still serve the purpose.
Here is a closer look at the 1UZ sleeve. Noticed any thing
different from the 3UZ?
Now you can start to noticed the ISS in the 1UZ is much larger.
The ISS is much larger in the 1UZ.
Here is a picture for referrence on the 3UZFE. Once again
the ISS for the 3UZ is .574"
The ISS for the 1UZ is .719". The ruler above and below is
just a reference. However, I used a caliper for all the
Below picture is very interesting. I put 1UZ heads into the
3UZ block. Its a direct bolt on.
The above and below pictures are the first of it kind. This
combo is possible with minor modification on the 3UZ pistons.
The sleeve inner diameter for the 3UZ is 3.579" and the inner
diameter for the 1UZ is 3.433". The sleeve thickness
between the two engine is the same .187".
Here is a side view of this combo. So, what do we learn from
|1UZ Vs. 3UZ Block
|Inter-Sleeve Space (ISS)
|Sleeve Bore Size
|Sleeve Thickness/Bore Size Ratio
We I learned is that the 1UZ and 3UZ have the same aluminum block
except the sleeves. The 3UZ has a larger sleeve then the
1UZ. However, the thickness of the sleeves for both
engines are the same. Due larger sleeves, the 3UZ have
small ISS. Now the question is having small ISS weaken the
block? ISS means less support for the sleeves and this is
very essential during high hp application.
On the other hand, I wonder how would the 1UZ perform with 3UZ
heads? I think that is the optimal combination. Even
though its only .3 liter smaller but it has stronger block,
stronger rods and beefier pistons. If we can get 3UZ
heads, then the flow would be much better. Since the
engine parts and interchangeable, therefore the mix and match
combination would be endless. What do you
think? Wanna input your opinion? You can post it
Now the question would be which motor is stronger even they have
the same sleeve thickness. The Sleeve Thickness/Bore size
ratio is .0544 for the 1UZFE and .0522 for the 3UZFE.
Therefore the 1UZ has greater ratio for the given bore size.
Another word the 1UZ has more sleeve ratio then the 3UZFE.
Note: ISS is the distant between two sleeves.
Edge to edge. 1UZ have large ISS and therefore more
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