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The engine and head in question is an rb25 head/30block.

The head is off a R33 RB25DET and has VCT.

1. Can I use GTR solid lifters replacing the RB25 hydraulic lifters?I would be using cams to suit solid lifters of coz, I assume I would need the GTR followers too.

TOMEI lists different ones for the 25 and 26. http://www.tomei-p.co.jp/_2003web-catalogu...r_engindex.html

This looks like an expensive exercise.

2. Are VG30 and CA18 lifters hydraulic as standard?.

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You wouldn't be able to do a straight swap for the rb26 buckets as they will sit down too deep in the lifter bore. The 26 also runs a different retainer as it has a recess in the top to locate the adjustment shim. The 25 has the HLA built into the bucket and the tip of the valve sits a fair bit deeper in the head in relation to the base circle of the cam than the 26 valve does.

There are also 2 different spring setups on the RB25 so you need to be careful that you order to suit what you have.

I would say the aftermarket solids for the 25 are designed to take up this extra distance with a longer "foot" inside the bucket that sits down onto the shim. Do they also sell the retainers and shims with the cam and buckets? The standard retainers have no way to locate the shim.

Yep, the CA18 and VG both run hydraulics.

You wouldn't be able to do a straight swap for the rb26 buckets as they will sit down too deep in the lifter bore. The 26 also runs a different retainer as it has a recess in the top to locate the adjustment shim. The 25 has the HLA built into the bucket and the tip of the valve sits a fair bit deeper in the head in relation to the base circle of the cam than the 26 valve does.

There are also 2 different spring setups on the RB25 so you need to be careful that you order to suit what you have.

I would say the aftermarket solids for the 25 are designed to take up this extra distance with a longer "foot" inside the bucket that sits down onto the shim. Do they also sell the retainers and shims with the cam and buckets? The standard retainers have no way to locate the shim.

Yep, the CA18 and VG both run hydraulics.

Spot on, the only thing I can add is when doing a solid conversion on an RB25 cylinder head we use GTR valves, GTR valve guides, GTR valve spings (std or aftermarket), GTR collets, GTR retainers and (obviously) GTR buckets. :rant:

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