1990 1UZ Cylinder Heads on 2001 3UZ Block
- Thread starter Stock430
- Start date
The 1UZFE EGR Delete Kit is available for sale here.
lexboosted
New Member
Short answer: it'll physically fit but you'll need to address a few things.
The 1UZ non-VVTi heads will bolt to a 3UZ block. The bore spacing and head bolt pattern are the same across the family. What changes is the combustion chamber geometry and compression ratio -- the 3UZ runs higher static compression than the early 1UZ, so mixing the two affects where you land. You'll want to calculate the final CR before committing, especially if boost is in the plan.
The other thing to watch is the cam phasing. The 3UZ block is designed around VVTi heads. Running non-VVTi heads means you lose that system entirely, which isn't necessarily a problem for a performance build on a standalone ECU but it's worth knowing going in.
What's the goal -- N/A build, forced induction, or a budget refresh using what you have on hand?
The 1UZ non-VVTi heads will bolt to a 3UZ block. The bore spacing and head bolt pattern are the same across the family. What changes is the combustion chamber geometry and compression ratio -- the 3UZ runs higher static compression than the early 1UZ, so mixing the two affects where you land. You'll want to calculate the final CR before committing, especially if boost is in the plan.
The other thing to watch is the cam phasing. The 3UZ block is designed around VVTi heads. Running non-VVTi heads means you lose that system entirely, which isn't necessarily a problem for a performance build on a standalone ECU but it's worth knowing going in.
What's the goal -- N/A build, forced induction, or a budget refresh using what you have on hand?
