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how hard would it be to build the bottom end yourself? im soon to be going through the rb30 conversion (going to take my time on it though do bits and pieces myself etc, and i was thinking maybe to save some dough i could assemble it myself? (with the help of a mechanic friend ofcourse) the only thing would be is id have to get the block prepped and crankshaft balanced as well as the rods and pistons balanced, then assemble it together and then get take it to work shop get them to hook it all up i.e. take out old block put in new one........what do you guys reckon it can be done or is it a total waste of time and not worth the hassle?

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total waste of time and not worth the hassle?

Yeah f**k that mate

By the time you do it, then transport it, waste time when you can be making money at work - much easier to pay someone who knows what theyre doing IMO

Good luck with it :P

Cummon guys dont be so down. Go out and buy a good engine reconditioning book, and study it, bear in mind you will have to spend about $1000 on tools assuming you already have the simple tools like spanners and sockets, but youll spend that money on labour anyway. Get the motor machined up and assemble yourself, checking everything twice. Hire an engine crane for the weekend_or buy one, there like $200 on ebay) and swap them yourself, save you money and give you twice the satisfaction.

If you have some idea of what your doing, and have seen it done before do it your self.

Its really not that hard, just make sure you have a good torque wrench, piston ring compressor, few sockets and a ratched, and a clean area to work in.

Have everything ready and it should only take you a few hours to assemble. Maybe speak to a professional that is qualified and knows what they are doing to get a few tips and tricks.

Me and my dad assembled my forged RB30 bottom end, all brand new stuff went into it. Fair simple and straight forward, but my dad as assembled many engines in the past.

Everyone has to start somewhere though..

Edited by abu

+2 on Adriano :)

I've only done a 20det, but yeah

You'll need a few tools, clamps, piston ring clamp(easy to buy from ripco or stupidcheap), torque wrenchs, various sockets, razor blades

basically strip the block down,

take the crank, clutch, flywheel and harmonic balancer to an engine shop, get then to grind and balance it for you(just a light grind, it's already nitrided from factory so you don't want to weaken it) or get a heavy grind and a nitride to make it even stronger, think the nitriding cost me $150 when i had it done here in NZ, balancing $350

get the block acid dipped, then honed if needed, shouldn't be too much, about $120 for the hone(at $20 per cylinder, might get it less) $65 for an acid dip

then use follow the engine manual procedures on putting everything back in with the correct torque settings and so on,

Should take you a weekend or less to put it back together and you'll have a feeling that you've accomplished something, also skim the block so it's flat, and the head, so when you mate them together the seal will be perfect

I'd suggest while you have it apart as well, repaint the engine block, just a nice grey or black ;) and replace the frost plugs, clean the sump and respray it in black engine enamel and remove all old gasket, put new gasket on, I reckon just go for it, if you are really worried buy an old RB30 or RB20e for like $50 and just pull it apart, then put it back together for fun or even an old 4 cylinder as cheap as you can get :)

+2 on Adriano ;)

I've only done a 20det, but yeah

You'll need a few tools, clamps, piston ring clamp(easy to buy from ripco or stupidcheap), torque wrenchs, various sockets, razor blades

basically strip the block down,

take the crank, clutch, flywheel and harmonic balancer to an engine shop, get then to grind and balance it for you(just a light grind, it's already nitrided from factory so you don't want to weaken it) or get a heavy grind and a nitride to make it even stronger, think the nitriding cost me $150 when i had it done here in NZ, balancing $350

get the block acid dipped, then honed if needed, shouldn't be too much, about $120 for the hone(at $20 per cylinder, might get it less) $65 for an acid dip

then use follow the engine manual procedures on putting everything back in with the correct torque settings and so on,

Should take you a weekend or less to put it back together and you'll have a feeling that you've accomplished something, also skim the block so it's flat, and the head, so when you mate them together the seal will be perfect

I'd suggest while you have it apart as well, repaint the engine block, just a nice grey or black :) and replace the frost plugs, clean the sump and respray it in black engine enamel and remove all old gasket, put new gasket on, I reckon just go for it, if you are really worried buy an old RB30 or RB20e for like $50 and just pull it apart, then put it back together for fun or even an old 4 cylinder as cheap as you can get :blink:

Thats a good break down of whats required.

A full gasket kit would make things very easy, make sure you replace all gaskest with new ones.

I will probably sell my piston ring compressor if you wanted to buy a good 2nd hand one to do the job. Only been used once, still in mint condition. Saves you buying it new :)

i went into re-building my 25 with only basic knowledge (and a decent memory to remember where everything goes). i had a mechanic guiding me and i

followed the workshop manual when i had any doubts.

i went in with 0 engine building knowledge and came out of it with plenty.

i took it as a learning experience and it was one of the best decisions i have made.

TOOLS and SPACE.

if you don't have them, and don't want to spend about $1K to get them all, then don't bother.

if you think oh the bottom end if only worth $50, I'll just give it a go, you're gonna get the shits with all the trips to bunnings and supacrap stores.

as mentioned, get the engine manual and see what tools are required, see what you have and what you need.

check the prices of what you need and see if it's worth it.

I had plans to do my own when I was in Sydney as my mechanic of many years said I could use a corner in his workshop and all his tools as I needed.

that would have been easy and if you f**ked up, you only f**ked up a $50 block.

but if you have to invest in tools, make sure you think it's worth it.

Its really not that difficult. I helped/watched my friend built his holden 355 stroker motor. You need some nice outside mics, dial bore indicator, feeler gauges. He got the machinist to put the pistons on the rods as he has a piston press and that makes it basic as.

All motors are not really more difficult then the other especially not including doing the head(s). Check clearances between mains, big end, small ends, piston to bore, file fit ring gaps, check crank end float and i suppose you call it end float of the rod big ends(?) On his motor the rods had to be machined a little to increase this clearance. Then check oil pump etc, recommend using bolt stretch gauge not just torque is you are using studs for mains etc.

My next motor i will defiantly build with the help of him.

Also the main thing is be clean clean clean. Wash the bores down, then get perfectly white rags and wipe them down, if they dont come out white clean them again, and repeat. Small metal particles get stuck in the bore and can decrease motor life.

Happy building

Edited by GTR1993

i have built a ford 4.0ltr motor out of a ba for school (trade school) to specs, measurements, tolenrences etc.. It wasnt that hard, quite simple.. But i am still a bit iffy about building my own motor and getting it to make and handle power..

Anyone able to clarify the differences? like how much more detail and how much harder it is to do?

Building a motor is simple, the tools needn't be the best except the torque wrenches must be good and accurate.

Otherwise spend some time learning a useful skill that isn't just cheque book performance and telling everyone what a great motor (insert workshop name) built.

You need to research what you want out of the motor, spend time gathering the parts and the tools for each step, understand how and why things are assembled in a particular way, talk to people that build engines and ask about preparations and consumables like what grease and sealant to use (in an RB I use the head gasket and that is all) and most of all find a good machinist that will talk about what and why you need things done and then get them to do it if they have been a great advisor.

Finally, PATIENCE!!!

Take the time, don't rush and while the impoverished idiots brag about how much and engine build cost you can smile quietly and have spent what you saved on extra goodies, or fuel, or at least had it running much sooner than waiting on their highnesses at the workshop to get around to it.

Building a motor is simple, the tools needn't be the best except the torque wrenches must be good and accurate.

Otherwise spend some time learning a useful skill that isn't just cheque book performance and telling everyone what a great motor (insert workshop name) built.

You need to research what you want out of the motor, spend time gathering the parts and the tools for each step, understand how and why things are assembled in a particular way, talk to people that build engines and ask about preparations and consumables like what grease and sealant to use (in an RB I use the head gasket and that is all) and most of all find a good machinist that will talk about what and why you need things done and then get them to do it if they have been a great advisor.

Finally, PATIENCE!!!

Take the time, don't rush and while the impoverished idiots brag about how much and engine build cost you can smile quietly and have spent what you saved on extra goodies, or fuel, or at least had it running much sooner than waiting on their highnesses at the workshop to get around to it.

thats an excellent point. there are ALOT of people here who let their cheque books do the talking and think they're #1 because theyve got all the expensive parts.

ask them an engine question and they show their true 'more dollars then sence' attitude.

dont become one of those dummies mate.

i too would love to do this my self but lack the confidence and knowledge in doing it... but looking at some of the prices listed and seeing how cheep you can get an rb30 for it doesnt seem like too much money will be wasted if all goes bad any way

i too would love to do this my self but lack the confidence and knowledge in doing it... but looking at some of the prices listed and seeing how cheep you can get an rb30 for it doesnt seem like too much money will be wasted if all goes bad any way

exactly what i was thinking, 50 - 100 dollars doesnt matter much if you stuff up the block give it another shot, ive been around some shops and they were asking a minimum of 5000 dollars (headwork included) + the price of buying the bottom end parts this will probably be alot cheaper, looking at maybe 3000 total in parts and machining , which rb30 block would i be buying so i dont need to tap (make) the holes for vct or something :S

The problem generally itsnt say the block is only 100, its the machining that adds up. Once you bore and hone each cylinder (cheap) line hone with torque plate, balance everything up can cost over 1000 for your bottom end. Spin a bearing and junk the block, then you gotta get another block, machine it, regrind crank etc. Its not a massive cost but more then 100 dollar block.

hands on experiance is the absolute best.

everyones a keyboard mechanic, but get that person behind a motor and see how far they go.

even if you go as far as buying an rb30e engine for example, pulling it all apart, looking at how things work/ move etc,

and putting that engine back together you will gain a world of experiance. much more than reading forums

and much more fun aswell.

when it comes to building your engine.. why the f*k not?? what you got to loose except a few dollars. and by the end of it

youll be bloody proud, even if it spins a bearing or watever, i guarantee you youll never make that same mistake again on

your next build. youll learn from it greatly.

and what ive found is when i go to the major machine shop, head specialist, builders here, i find that the jap tuner who says yep ill build

your engine for 6grand send your bloody engine to these guys anyway. cut out the middle guy do some driving around your self

and youll save a lot.

just keep in mind you are as good as your tools,

be bloody extra clean with everything

double check all the clearances and torque specs

keep the manual close to your heart

and have a good knowledgable on speed dial haha

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