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Rb30 Engine Block For Rb26 Conversion

leeroy_25

By leeroy_25,
in Engines & Forced Induction

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leeroy_25 Community Regular

leeroy_25

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Hi there guys' Today I finally took delivery of my RB30 engine blocks from Australia! I am in the UK and have been interested to do the conversion for a while.. An opportunity came up so I took it.. After a lot of research and advise I was told the best block was the late non turbo block which would give a good compression ratio with the rb26 head and would also have the correct oil feed and returns already in the side ready to accept a turbo conversion. After much looking around Australia I tracked down a company with a couple of blocks and they said they were both the correct ones with the oil feeds etc.. However when they arrived today and I checked them out I found only one has the oil feed and returns in the side! Would I be correct to think this is not a major problem and I can just machine the holes in and tap them accordingly? Is there anything else the block will be missing that could be a problem or I need to be aware of?

Thank you in advance

Regards

Lee

P.S. i'll think i'll be visiting here a lot of the winter!

Guilt-Toy Grand Master

Guilt-Toy

Posted
Posted

how many blocks did you get?

Yes you can machine them to suit turbo with no issues.

Hi there guys' Today I finally took delivery of my RB30 engine blocks from Australia! I am in the UK and have been interested to do the conversion for a while.. An opportunity came up so I took it.. After a lot of research and advise I was told the best block was the late non turbo block which would give a good compression ratio with the rb26 head and would also have the correct oil feed and returns already in the side ready to accept a turbo conversion. After much looking around Australia I tracked down a company with a couple of blocks and they said they were both the correct ones with the oil feeds etc.. However when they arrived today and I checked them out I found only one has the oil feed and returns in the side! Would I be correct to think this is not a major problem and I can just machine the holes in and tap them accordingly? Is there anything else the block will be missing that could be a problem or I need to be aware of?

Thank you in advance

Regards

Lee

P.S. i'll think i'll be visiting here a lot of the winter!

leeroy_25 Community Regular

leeroy_25

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  • Author
Posted

Thank you there.. That is very good news indeed!! I thought that would be the case but figured I would check first!

I got two blocks.. one as a spare. I may sell it on once I have templated the holes into the other block! Is there anything else the block missing te oil feeds will be short on? Or is it all the same other than that?

Thanks again

Lee

leeroy_25 Community Regular

leeroy_25

Posted
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Posted

Hi Guys

The shippng was the biggest expense! Cost nearly 拢800! More than the blocks themselves!

R.I.P.S and some other dude on the UK forum came back and told me the blocks were scrap and no good for turbo applications.. then some other guy has told me hes has done a few like this! What's what?! Both the guy's that told me they are scrap normally sell blocks themselves!?

Personally I cannot see what can be that different.. as long as the pistons, rods, crank etc are the same and I can put the oil and water feeds and returns in then all should be okay right? I will also check the block front face is smooth above the pump is that was the first thing I looked at.. I assume worst case though I could also machine this area smooth?

Cheers Guys

Lee

unique1 Mentor

unique1

Posted
Posted

the flat spot for the lower tensioner is actually BELOW the water pump, i got mixed up and found out it was a s1 after i bought it. Ended up welding up the area and grinding it flat, engine is about to run in a couple of days now so ill see how it goes, shouldnt be a drama at all.

leeroy_25 Community Regular

leeroy_25

Posted
  • Author
Posted

Would you be able to post a pic of the mod you did no the front of the block? I was aware that the smooth area needs to be below the water pump but I have had the cover off to check that yet.. sounds pretty much like I have a series 1 block though! Doh! Oh well.. where there is a will there is a way! Is there an option to put the tensioner somewhere different. I presume if you had to weld up the front face it's not just a case of it being a rough cast finish that needs machining.. but it is the wrong shape?

Cheers Guys.

So much more positive than feedback I have had elsewhere!

R34GTFOUR Mentor

R34GTFOUR

Posted
Posted (edited)

the oil/water feeds are easy to do, definately no worries there. Its just nice to have the stock holes already pre-tapped ready to go, but i wouldnt go throwing the blocks out just yet haha

have a read of the rb30 DOHC guide, it tells you everything you need to know and it has pictures to show you the mounting positions for the tensioner.

Edited by R34GTFOUR

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