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Can anybody tell me whats involved in converting the 25 hydraulic valvetrain to the 26 setup' Is it simply a matter of 26 lifters and shims or is there more involved?

You need to get a tomei (or other)kit, as the valve height of a 25 and 26 is completely different

You need to get a tomei (or other)kit, as the valve height of a 25 and 26 is completely different
Strange

The head that I have at the moment is a 25 that's been modified to run GTR cams, and the GTR valve stems etc went straight in.

Is this just because I'm running the right cam for those valves etc?

Strange

The head that I have at the moment is a 25 that's been modified to run GTR cams, and the GTR valve stems etc went straight in.

Is this just because I'm running the right cam for those valves etc?

Cam's aren't tied to the valves. The valves are tied to the lifters though...

ep096_01_hilift-cam.gif

That's how a rb26 lifter is, notice how the valve goes pretty high into the lifter and the actual lifter is very short

ep096_03_nor_l.gif

Notice the length inside the lifter? that is how a rb25/rb20 lifter is set up. because of the length difference rb20/25 valves have that length difference taken off compared to rb26.

Edited by klh6686

The RB26 valves stems are much longer than the RB25 w/hydraulic lifters. The RB26 exhaust valves are even longer than the RB25 NEO exhaust valve stems, but the NEO intake valves are longer than the RB26's. In short, there's no easy way to go about converting to solid lifters with an OEM parts mix. A kit is your best bet.

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