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Hey,

I pulled down two rb25 det blocks...one for a rb30 build and the other just for a light rebuild for the race car while the 25/30 is in progress. I have some photos of the blocks to confirm about oil restrictors. One block is a s1 and other is s2. I had a piece of 1.56mm m/s tig electrode and i could not fit it down either of the two oil feeds. Both of these motors were dead std when we got them...one from car we already owned and one I picked up from down the coast which came in dead std form 2nd hand. Now If the restrictors are 2.4mm then shouldnt i have been able to fit the electrode down the feed? To me they look about 1.5mm, after i tapered the electrode tip abit it would just fit into the feed. Verniers verified 1.5mm holes.

Remember everything on these engines is std..internals/externals. So im lost.

Or am i confused with whats what here?

Cheers.

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will watch this thread ..

but on the tomei web site they sell the restrictors, and only thing they say about the rb25 is that you shouldn't use them if still using lash (hydrolic) lifters..

interesting..

was looking at my rb30 and rb25 blocks. i thought the rb30 ones were bigger than the rb25 (visually only)

Im pretty sure i read somewhere 2 X 2.4mm hole std for rb20 and 25. Im pretty damn sure these engines are both std and have 1.5mm holes in them.

Yeh i know the tomei site doesnt recommend using them with the hydraulic followers...but SK recommendations have been noted in the rb30 thread regarding oil restrictors.

Has anyone else opened up a 20/25 to find 1.5mm holes in their feeds?

Bloudy Cubes hey lol...leading us all astray. Unless he just got told that from his engine builder and someone got confused somewhere along the way.

So i guess you would still just block one off as per SK specs.

Edited by r33_racer

was the Rb30 block using a 1.8mm restrictor as per his measurements?

this is something i have been tossing up over the build, still cant get a good answer on what to run.. might just run an N1 with 1 feed of 1.5mm...

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