1UR Engine
- Thread starter Lextreme II
- Start date
The 1UZFE EGR Delete Kit is available for sale here.
Did I miss something? The block looks like a single casting to me, however as you said, the heads do have a separate camshaft housing - not sure what Toyota's rationale is for that - perhaps to provide replaceable wear surfaces?
Also noticed they've reverted to a roller rocker design for the valve train, with hydraulic lash adjusters. I'm guessing the initial lift profiles were too aggressive for direct actuation of the valves? Maybe a camshaft guru could jump in and comment on this. Seems odd that the company who is best known for its direct actuated DOHC engines has gone to a rocker arm design.
Instead of having main caps and an oil pan, the entire bottom half of the block is another piece. The new Honda K-series engines are this way as well, and it's a very strong design. Kind of like a main girdle on crack.
I agree though, direct injection is too new to have any fun with on the tuner end of things. Nice to see some new engine progress though, and they are making some pretty good power from the factory!
do you have a pic of that?
TundraEddie
New Member
More info please :tongue2:
Lextreme II
Active Member
LOL.... Ok... Here is a sheet of the engine spec. Since the all new 1UR engine is using timing chain. Would it be little louder then timing belt?
Lextreme II
Active Member
11.8:1 is pretty high. Its not much room for FI for sure. Due to high compression any problem with the timing will destroy the whole engine. I think that is why they used timing chain instead of timing belt. I have some VVTi engine with valves (the the whole engine) destroy because of faulty timing (broken timing belt, wrong timing belt installation or other timing related issues) I wonder how many miles you need to change timing chain?
not often is my best guess. the (steel) timing chains are pretty tuff. Ferrari uses timing chains in their newest V12(the one in the Enzo and the new 599 GTB), thats good for something. the only timing system stronger than the chain is gears, used in, buess what, endurance racing. ive never heard of a racecar having timing problems.
UZZ30-Québec
New Member
amazing, the engine block is in 2 pieces just like mazda's KL series engines. The camshaft housing is pretty cool too, looks like a strong assembly made to handle a lot of stress. say "thank you direct injection" for the 11.8 comp ratio, the pre-ignition problems are reduced a lot.
Did I miss something? The block looks like a single casting to me, however as you said, the heads do have a separate camshaft housing - not sure what Toyota's rationale is for that - perhaps to provide replaceable wear surfaces?
Also noticed they've reverted to a roller rocker design for the valve train, with hydraulic lash adjusters. I'm guessing the initial lift profiles were too aggressive for direct actuation of the valves? Maybe a camshaft guru could jump in and comment on this. Seems odd that the company who is best known for its direct actuated DOHC engines has gone to a rocker arm design.
turboandrew
Member
I thought it was odd that the left and right bank have different valve timing ranges. Also, notice that they publish the weight now. How does 511 lbs compare to the 3UZ?
striker
New Member
No direct injection is not used in F1, the video's around on google suggest that at least Renault is still doing it with Douche injection, which means that the injectors are suspended outside above the up and down moving intake trumpets.
the dynorun form that set-up recorded 20.002rpm MAX, offcourse compression is not known,
I wouldn't want a direct injected petrol engine for tuning, there's virtualy no aftermarket for bigger injectors and higher combustion temp than stock can easily kill them. also High rpm atmosation for tuning seems pretty difficult to get at to me.
If it was very much better power wise the motorcycle lads would use it and they don't. it is just emissions.
just a pitty about the rollerrockers though.
grtz Thomas
the dynorun form that set-up recorded 20.002rpm MAX, offcourse compression is not known,
I wouldn't want a direct injected petrol engine for tuning, there's virtualy no aftermarket for bigger injectors and higher combustion temp than stock can easily kill them. also High rpm atmosation for tuning seems pretty difficult to get at to me.
If it was very much better power wise the motorcycle lads would use it and they don't. it is just emissions.
just a pitty about the rollerrockers though.
grtz Thomas
Lextreme II
Active Member
TundraEddie
New Member
One of the Lexus engineers said the roller rocker design was to reduce friction and maintenance. I was going to pick his brain about the different valve timing,but we ran out of time because of a discussion about fuel economy,octane,and hybrids.
Instead of having main caps and an oil pan, the entire bottom half of the block is another piece. The new Honda K-series engines are this way as well, and it's a very strong design. Kind of like a main girdle on crack.
I agree though, direct injection is too new to have any fun with on the tuner end of things. Nice to see some new engine progress though, and they are making some pretty good power from the factory!
Roller rockers
The reason for the roller rocker design is to have a cam design with minimal lift but longer duration. At least that was the rational for the roller design for the 1gr v6's, which use a similar setup, so I would assume the cam setup on the 1ur is for the same reason.
The reason for the roller rocker design is to have a cam design with minimal lift but longer duration. At least that was the rational for the roller design for the 1gr v6's, which use a similar setup, so I would assume the cam setup on the 1ur is for the same reason.
do you have a pic of that?
