Shim over, or under bucket...or shimless?

[cribbj]

Paul Carey is running a Nissan RB26 shim/retainer/collet setup in his racecar with 2UZ buckets. It would be interesting to get photos of this, or another RB26 setup.

He tried the 2UZ retainers, but his Crow springs are larger OD than the 2UZ springs, hence the need for the larger RB26 retainers.

I don't know if 3UZ springs are the same size as 1UZ, and if so, maybe their retainers with the recess for the valve shims would have worked? Anyone have good pics of the 1UZ VVTi and/or 3UZ retainers, buckets, shims, etc.?

Here's a pic of a 2UZ retainer - you can see the recess for the shim, and also how small the diameter of the spring/retainer is.

My idea a few posts earlier about using shimless buckets and substituting shims for lash caps won't work with the stock 1UZ retainers, as they aren't setup with a shim recess.

 

[cribbj]

So who makes a titanium retainer with the shim recess on top for a shim under bucket application?

 

[XR8tt]

I'm waiting big time for a solution / good combination..
Anciety !!! I have changed my cam specs due to better buckets.
I think there are titanium retainers for RB26 Nissan GTR that fit, also better valve springs can be fitted..
http://www.lextreme.com/forums/showthread.php?t=6810

From above..
Our application is racing obviously. We run .470" lift with 320 degrees duration, 2UZFE buckets and 100 lb Crow single race springs.
I used the RB26 valve spring retainers because the 2UZFE retainers are too small in diameter (2UZFE springs are much smaller than 1UZFE) and did not fit the Crow springs. The RB26 retainers fit perfectly and were cheap and on the shelf at the local Nissan dealer. When we went to assemble the valves, we found the 1UZFE collets placed the retainer at the wrong height - RB26 collets fixed that. Interestingly we tried the RB26 bucket in the hole - and it fits exactly (and has a larger area under the bucket in the boss area for the shim). We had to mill .040" out of the spring base area, because the springs coil bound .020" after max lift (.060" recommended). With custom made shims the assembly went together nicely - although we do not run valve seals. You would have to check that clearance first. With only one run on the engine, we will be watching these details and wear patterns closely.