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So, I've reached the point that (I assume) many others get to with a RB26: The block is showing signs of a coolant leak just below the exhaust manifolds: it's cracked, and not repairable from what I have been told. It still drives fine for now, and the crack is minor, but I can't push it any further without getting a new block or engine...

So far, i have just under 300awkw from cams, N1 turbos, Power FC, baffled sump, etc and a fuel system that will support a heap more power.

What I am chasing is more midrange torque/power: I'm not concerned with the paek power figure: bench racing isn't my game. I want a car that I can take for a blast on the weekends, and an occasional track day.

The brakes and suspension are inplace to support a significant performance increase, but I'll need to address the gearbox (R32 GTR unit, but it's getting tired), and potentially the diffs/driveshafts (not sure what sort of redundancy is built in? It currently runs R33 GTR front shafts, R33 diffs, and modified rear shafts)...??

The engine dilemma is my main concern, because I keep getting advice that says to use different approaches: do I build a "RB28" using a N1 block and aftermarket (JUN/HKS/TOMEI) internals, or do I buy a crate engine? Obviously my current (R34N1) turbos will need to be replaced, but I need sound advice for/against either option.

I believe what I'm looking for will be an engine/turbo combination to support 600-700HP at the engine, with a good, meaty midrange, and a gearbox/gearset to suit ( I was thinking PPG 1/2/3 gearset, but any advice would be appreciated!).

Is there anyone here who has performed a build/crate engine fitment who has had favourable/similar results??

I need some direction!

Well you're starting with a new block regardless, so a 2.8 will make sense because it's just easier to make big numbers. If you know exacly how to set it up on a 2.6 crate motor then go for that, but it will need bigger cams and turbos (and lag) to make up for less displacement.

Oh, and you're chasing madrange. A stroker is where it's at then.

Add up the cost of block+rotating assy then compare it to the crate motor. If there's a ridiculous gap in price then it will be worth keeping your old head+sump. If not, then a crate motor will be worth serious consideration (but if you plan to forge it then the pricetag will begin looking ugly).

Well you're starting with a new block regardless, so a 2.8 will make sense because it's just easier to make big numbers. If you know exacly how to set it up on a 2.6 crate motor then go for that, but it will need bigger cams and turbos (and lag) to make up for less displacement.

Oh, and you're chasing madrange. A stroker is where it's at then.

Add up the cost of block+rotating assy then compare it to the crate motor. If there's a ridiculous gap in price then it will be worth keeping your old head+sump. If not, then a crate motor will be worth serious consideration (but if you plan to forge it then the pricetag will begin looking ugly).

Yeah: forged is a foregone conclusion: I'm all about reliability/over-engineering...

speaking from experience in doing a stroker rb26, dont bother for the money i'd choose a rb30 bottom end built with a 4wd sump adaptor and will cost a whole lot less than the hks kit for sure and provide better midrange power.

I was under the impression that the RB30 was a major hassle to fit?? Not contradicting you, but I read a thread in which SK intimated that it was a major engineering feat...

In fact, my old man wanted to do the RB30 conversion when we started this whole project, but at face value, we were told it was too costly/difficult...

Please correct me if I'm wrong...

I was under the impression that the RB30 was a major hassle to fit?? Not contradicting you, but I read a thread in which SK intimated that it was a major engineering feat...

In fact, my old man wanted to do the RB30 conversion when we started this whole project, but at face value, we were told it was too costly/difficult...

Please correct me if I'm wrong...

it not difficult at all just requires the fitment of the 4wd adaptor kit available from someone like www.proengines.com.au he even does complete ready to go bottom ends ready to bolt your head on for $7000 (just checked i think 4wd adaptor is extra), a hks stroker kit is gonna cost a hell of alot more overall i can assure u of that.

n1 block 2k

hks kit 7k

machining 1k

jun oil pump 1k

bearings $250

seals and core plugs etc $150 or so

main studs $300

head studs $300

assembly ???

rb30

the 4wd adaptor kit is $900 plus fitting, probably a couple of 100 bucks (this comes with suitable oil pickup so no need for sump mods)

block $100

pistons and rods $2100

main and head studs $600

machining $1000

jun oil pump $1000 or $400 for n1 pump

assembly ???

once the adaptor is fitted u need another front tensioner installed which is a simple job and the head stud holes have to be tapped bigger to suit rb26 studs (from 11mm - 12mm from memory).

best to read the rb30 into gtr thread to get an idea, its definately not as bad as some people make out, and sure as hell saves alot of money over the japanese kits with the same, if not better results.

im building a rb30/26 at the moment with stock internals as well as keeping my jun 2.7L stroker engine and gonna compare the 2 once and for all :D The jun stroker kit is 10k alone (crank, rods and pistons only) so thats definately not cheap.

personally i'd be going rb26/30 with a set of 2860r-5 turbos and limit power to around 500hp at wheels and then u wont need to upgrade the gearbox which isnt cheap either. I run a ppg 1st-5th straight cut dogbox and its not an ideal street friendly option and maintainence costs are on going. All this is also in a stagea as well and im pulling the stroker motor out to go in a track gtr and the 26/30 is gonna be the daily runabout

Edited by unique1
Whats the budget?

At this stage, budget is open: I am assuming a crate motor + turbos +gearbox will cost around $25k-$30k... I'd prefer to spend less, but if that's what it takes, so be it... realistically, I know I'm up for big $$...

my stroker setup with bolt ons has cost a hell of alot more than your estimates and then the gearbox on top of that

rb30 isnt a straight fit i know but for the $$$ its worth paying abit for fitting adaptors etc then paying the stupid costs of japanese branded parts when u dont really get any benefits unless u wanna go over 700hp at the wheels then the billet crank etc makes it worth while.

just my personal opinion after going all out on a stroker kit and regretting it now i dont wanna run a laggy arse turbo i could have got away with spending 1/2 the money i did and have as good results.

Edited by unique1

http://www.gtr.co.uk/forum/upload/52458-rb...-lots-pics.html

a guy in the UK put the rb30 into his r32 gtr

its a pretty good read, it doesnt look easy but still i think its worth the effort,

btw i wouldnt say its a 'major engineering feat' its not like you gotta put a man on the moon

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