another 1uz head on 2uz block questions thread

[Paulwolf]

I have a 2uz, which i am building for an offroad racer

it needs to have as much torque as possible, and about 450 - 500 hp

I have decided on using the 2uz bottom end - already have it
I have decided to use an intercooled m112 - already have it

I have pulled the heads on the 2uz, and have bought a set of 1uz heads

I have been trying to do some math to work out the best way of making this work,

I know - i will need different pistons
- the 1uz heads have 43cc chambers,
- head gaskets from my 2uz were 1.15mm thick
- 2uz pistons are 0.65mm above the block
from previous posts, dish in piston is 29cc, but i dont know if this takes into account the dome portion or not. dome rises some 3.2mm above block and has dish in the middle
has anyone measured the 2uz piston crown relative to the block at TDC?
can anyone tell me the combustion chamber volume of 2uz head

trying to work out the stock CR for this motor, (I know it is supposed to be 9.5)
then what I need i need to do to a piston to clear the 1uz head and still maintain 9:1 CR or better

lextreme, I know you have done this?

Paul

 

[4U2QUIK]

you don't want the 2uz block, it's junk in comparison to the 1uz bottom end. It's only 2 or 4 bolt main instead of 6, it has skinny ass rods and crap pistons.

 

[Paulwolf]

Thanks mate, I know all about the block. With 2 bolt mains it will still handle up to 1000hp.

My questions relate to the heads and pistons

Paul

 

[Paulwolf]

looks like the 2uz chamber volume is 40ccs

found a couple more old posts.

I will do some more calculations

Paul

 

[Paulwolf]

Found some more info on another lexus forum

Early 1uz pistons are basically flat tops
the 2uz piston - deck height is 33mm
so with the 43.5cc combustion chambers on the early 1uz, 9.5cc in the gasket (0.051"), zero piston to block height , i need 16cc dish (or valve reliefs) in the pistons to reach 9.5:1 CR

will this work or am i missing something?

would I be better off lifting the piston out of the block and making the reliefs bigger? like 0.8mm proud of block with 22cc dish (late model 1uzfe)

Paul