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RB26/30 build stock bottom end

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Ive bought a r32 skyline with a rb26/30 that has been built poorly and i assume didnt have the greatest tune as it was over fueling and only making 315rwkw at 20psi through a decent sized single turbo. Ive pulled the motor out because i found fuel leaking into the oil, my guess is either from over fueling or possibly even damaged injector seals (yet to inspect seals). the bore looks mint still but was definately bore washed. was hoping to chuck some fresh piston rings in and reassemble. Really not looking for much more than 300+350kw as its just a street car. Can anyone tell me if theres anything i should do before reassembling (headstuds maybe). Dont really want to go down the forged track just yet, really just want to get it back together and enjoy it while i save for all the parts to rebuild forged, balance crank and more power. If anyones got experience with 30det builds any advice is appreciated.

Other than giving it a good eyeballing and measuring, don't forget to give the bores a light hone to ensure the new rings bed in properly.

Use a new belt, tensioner, etc - if there is ANY doubt about their condition.

If I’m only using stock parts what will I need to measure ? Also any idea what kinda figures I can safely pull from a stock rb30 bottom end ? TIA

Hi Danny

you will need to measure main and big end clearances

ring end gaps this should be about .018 on the top ring and 0.022 thousands of an inch on the sec ring this does vary with ring type (brand)

generally every part fitted should be measured but the above is a good start

Regards Ross

If its build with stock parts be sure to check the compression ratio.

the stock pistons combined with a dual cam head may result in very low comp ratios