1UZFE Vs. 2UZFE Bucket

[Lextreme II]

I got a chance to noticed the bucket differences between the two engines. I am not sure the valve stem length of the 2UZFE, but from what I see the buckets are different. The 1uzfe bucket is pretty much flat with no noticeable raise. However, the 2uzfe has about 1/16" raise. Assuming they both have the same valve stem length, then the 2uzfe should have greater lilft. I wonder if we can use the 2uzfe bucket on the 1uzfe heads for greater valve lift.

Beside the greater bucket seats, there seems to be an additional shim also. The 2uzfe and all the VVti heads have a space on the retainer for a shim. Check out the pictures..... The last picture is the 1uzfe bucket.

I wonder if we can use the 2uzfe retainers, shims and buckets on our 1uzfe heads for greater lift for more flow.... What do u think?

 

[1youZee]

So, if i understand this right, the 2UZFE is a shim under bucket design? that would be a great improvement allowing higher lift cams. Is the width the same as a 1UZ, what about the height?

 

[Lextreme II]

They are interchangeable. Yes, the 2uzfe have shims under the bucket and the bucket also have increase thickness which increase more lift.

 

[Lextreme II]

Here are some detail pictures of the two buckets. Noticed I put a 2uzfe bucket into the 1uzfe head.

 

[elhsupra]

Stupid question but....
If the 2UZ buckets are thicker, will it effect or prevent the valves from closing completely?
This looks like something I might have to try with the kelford cams

 

[Red Supra]

Shim under bucket conversion on early vv-t heads was mainly for lighter valvetrain according to Toyota. The later vv-t heads use buckets with built in shims.
There was no incident to my knowledge that a shim in a bucket ever ejected.

 

[Lextreme II]

I am thinking about using the VVTi retainer, shim and bucket on the 1uzfe valvetrain. This will provide greater lift.

 

[toad007]

I am thinking about using the VVTi retainer, shim and bucket on the 1uzfe valvetrain. This will provide greater lift.

Its not going to provide great lift. The lifter under the cam has no multiplication effect. It being taller is just going to make your valves not seat properly. Yes it will create more lift from the seat, but not lift as in total travel of the valve. It wont shut if this shim/bucket is taller than the stock ones and the cams are using the same base circle as stock. If I move my finger back and forth 2 inches with my hand in front of my chest, it moves 2 inches. If I move my hand out away from my body a foot, and move my finger 2 inches, it still moves 2 inches...Get the idea?

 

[Lextreme II]

I was also thinking about re-grinding the stock cams to compensate for the shims.

 

[cowboy bebop]

Or you could always go with shimless buckets. These are for a Toyota MR2, but fit MKIV Supras, so hopefully they should fit the 'uz-fe family of motors. Is that correct?

 

[Kiwi.in.aus]

??

Umm , I just thought I was missing something when reading this . LOL
You can't get more lift than what the cam lobe gives you regardless of the actuation system , the aqmount of travel is set by the cam lobe , also unless you add to the lobe first regrinding it won't actually give you more lift , just a different profile .

 

[Zuffen]

Kiwi,

By reducing the base circle diameter (the diameter of the cam before any ramp or lobe) you can set the bucket height higher. This will give you more lift.

If you machine 1mm off the back of the lobe (or the base circle) you can raise the bucket 1mm with the same valve clearance. This then means the lobe (which for sake of the argument is unaltered) will have 1mm more lift at the new bucket height.

You could end up with some problems if the base circle diameter gets too small and it starts to damage the follower.

 

[rytherwr]

Shims are for adjusting valve clearance on 2uzfe

According to my 2003 Tundra shop manual, the shims are for adjusting the valve clearance on the 2uzfe. There are a bunch of thicknesses called out in the manual and it tells you how to go about it.

 

[Kiwi.in.aus]

Quite right Zuffen !!

I think my brain went on holiday for a bit !!
Seems to happen a bit more often these days !!
I should think a bit harder before I punch the keyboard .

 

[ed_ma61]

regrinding base circles on bucket type vlave trains is bad...

 

[Red Supra]

regrinding base circles on bucket type vlave trains is bad...

Why? (10 letter min limit is gay)

 

[ed_ma61]

increases the acceleration profile of the cam lobe and stresses the bucket top, wall, and bore more

secondly, i havent looked at the 1uz in detail, but often there is fouling issues if the bucket comes up out of the hole - hits the bearing retainersurfaces and such...

 

[Zuffen]

ed,

You're right.

If we make the overall diameter too small and/or ramp angles too steep we will end up with more trouble than we need.

I can't see the shim under bucket is worth the agravation, cost or potential problems.

 

[Lextreme II]

I think few companies in Australia is doing the same thing. Adding shims for great lift.

 

[ed_ma61]

I think few companies in Australia is doing the same thing. Adding shims for great lift.

doesnt mean its a great idea...

of course theres a dodgy way to do everything... been there, tried that

edit: and add to that list of issues - increased side loads on the valve stems causing premature wear on the valve guides... which is compounded if you have ported the head and taken that bottom 5-6mm off the guide in the port

cheers
ed