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MAX you'd pay for this bottom end (RB31DET)

mr_rbman
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mr_rbman Grand Master

mr_rbman

Posted
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OK guys, i've been given an oppurtunity to get what i think is a pretty cheap RB31DET bottom end (block).

What i'm asking is the maximum any of you guys would pay for this, here are the specs:

-VL RB30 NA Block, deck has been honed and the bores have been made 20 thou oversize for the bigger pistons (3.1Litre)

-Hypa-tech pistons brand new and 20 thou over size (makes it a 3060cc I believe) Their semi-forged and ceramic coated

-Rods are standard but have been shot peened and balanced to make them all the same weight etc.

-Crank is standard but has been ground and balanced.

-Block has been grub screwed for strength.

-Has all new Welch plugs etc and all new bearings

-All the oil and water galleries have been cleaned and the oil galleries have been modified for better use for turbo's? (not sure on that one either)

-ALL it needs is an oil pump, water pump, sump and head obviously which i already have to complete the bottom end, everything is together and has all been done by a reputable engine builder here in Adelaide.

So my question is how much would you pay and any other comments are more than welcome!

Fitzpatrick Speed Works Mentor

Fitzpatrick Speed Works

Posted
Posted

theres about $700 worth of machining in preping a new engine on a rb30, and buy the sounds of it around $700 in parts assuming they are only standard type pistons... So I wouldn't pay much more than $1200.

StockyMcStock Proficient

StockyMcStock

Posted
Posted

they will be standard cast pistons, only new. grub screws in the crank are for the rod lubricating oil journals on the big end, nissan drilled big long holes to connect them and then bashed aluminium plugs in there to plug em up so oil wouldn't leak out (duh) and lose pressure. after a lot of k's they can become loose so you drill em out, tap it and put a 1/4" grub screw in there. stake it and you're done!

it sounds exactly the same as my block, you're looking at $500-$700 of prep work by a machine shop and up to a grand again for rebuild parts (rings, bearings, pistons, seals etc) so i wouldn't pay more than $1300 for it.

mr_rbman Grand Master

mr_rbman

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Posted

thanks guys. thats what i wanted to hear. the guy has offered me it for $750 so i'm going to go pick it up Tuesday

And by the way the pistons are 'HYPER TECH'

think i've heard of them before!

proengines Rising Star

proengines

Posted
Posted

There is a brand of pistons called Hypatec, they are hypereutectic pistons made by Right Way Piston Co. in Taiwan. theyre a nice piston but from what I know they dont make anything forged for the RB. There is a Hypatec liquid forged piston that is excellent but not available from what I know for an RB engine at all. They are made by pouring the liquid alloy into the die and forging it once it starts to solidify. This is the same way that Toyotas forged pistons are made and when you see some 1000hp-ish 2jz's they are awfully strong.

I've seen coated pistons for the RB30ET but not for the n/a engine. It's actually an anodising they use. Be careful if it has a slightly dished piston rather than a dome as you will have way to low compression.

It is a good buy, just depends if it fits your needs.

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