The Mafia's Povo Rb30 Build - Cheap, But Not Nasty - Some Real Simple Questions

[The Mafia]

Hey guys

I have a standard RB25 that is laughing at my 300rwkw. (Loves the water meth though). It has some small problems, like the sump gasket leaking, and the synchros need a service etc. Engine and gearbox have to come out to fix these problems, so while they are out, lets just put a RB30 back in there? lol.

So what I want to do, is install a standard built RB30 and sell off my Complete RB25.

What I have:

RB25 complete head, lightly ported.

RB30 NA Block complete Still built, only head off, only 160,000kms, hone marks still in bore.

GTR Oil Pump

Ok so here is my plan:

1. RB30 block dissasembled, acid bathed, xrayed, honed and decked slightly. Maybe a little more to raise the compression a tiny bit.

2. Drill and tap hole for New tensioner.

3. Head cleaned and reconned.

4. Grub Screw VCT oil feed in head, and do the internal VCT oil feed mod, block rear oil feed, 1mm restrictor in front feed.

5. GTR oil pump cleaned and checked.

6. Get crank checked. Fit crank collar.

7. Assemble RB30 Block with original pistons, rods, and crank. New Rings, main and big end bearings.

8. Bolt head on with Head gasket (not sure what I use yet)

9. New Water pump, timing belt, RB25 Harmonic balancer.

10. Screw cleaned up, milled, and sealed china copy side mount intake manifold onto head.

11. Install Injectors, Water meth, throttle body.

12. Install Exhaust manifold.

13. Install Turbo (GT3037) with a 0.82 rear housing.

14. Have exhaust modified, and intake piping fixed. Install big ass f**k off stupid twirly, duck whistle, fluttering blow off valve so women take their clothes off and jump into the car. Install Factory BOV, and plumb back.

15. Drop engine back into car.

16. Install Gearbox.

17. Run in on dyno, maybe just on the street.

18. Drive around.

19. Run 11's down the quarter.

20. Post a thread on SAU about it.

Questions:

1. What rings should I buy for the standard pistons? - Can anyone recommend any?

2. What bearings, and what clearances should I run?

3. Have I missed anything stupidly important or worth mentioning?

Car has Nismo 555's, GT3037, WMI, 600x300x75 IC, 3.5inch exhaust, Powerfc, I tune it, etc.

Currently making an easy 310rwkw+ on 20psi. Been like that for 2 years now, and compression tests are all still consistant and high. Wish I new if it had forgies or not, its a bit of a weird one to be honest with you. I'll have a look when I have the sump off.

Edited October 30, 2009 by The Mafia

[TiTAN]

while you are at it you might as well get the bottom end balanced (should only be about $250 or so for a shop to do it)

Edited October 30, 2009 by TiTAN

[The Mafia]

I was thinking about it, but do you think that is really necessary for 300rwkw and a povo build? Only be reving it to 7,000rpm, maybe a tiny bit higher if others think its safe to, and if the turbo has enough puff.

Edited October 30, 2009 by The Mafia

[r33_racer]

+1 for the balancing

You seem to have it all covered.

[STATUS]

balancing for sure cheap too $195

[CEF11E]

sounds loke a simple but effective engine.

If I was going to build one again, and i probably will shortly, I would use gtr rods prepped and a set of forgies and new rod bolts. but that would be to lean on it harder and shoot for 400rwkw. totally un nessacary power figure but I have all the supporting mods for it.

for your power figure it sounds like a good reliable combo.

my build had less effort put into it and pushes 320rwkw now and shows no signs of trouble. rev limiter set to 6700 now

[MBS206]

Way too much effort...

Check the deck on the block is flat... do the head mods, check head is flat... Bolt the two together...

[TiTAN]

sounds loke a simple but effective engine.

If I was going to build one again, and i probably will shortly, I would use gtr rods prepped and a set of forgies and new rod bolts. but that would be to lean on it harder and shoot for 400rwkw. totally un nessacary power figure but I have all the supporting mods for it.

for your power figure it sounds like a good reliable combo.

my build had less effort put into it and pushes 320rwkw now and shows no signs of trouble. rev limiter set to 6700 now

you cant use the GTR rods they are too short for a 30.

[TiTAN]

I was thinking about it, but do you think that is really necessary for 300rwkw and a povo build? Only be reving it to 7,000rpm, maybe a tiny bit higher if others think its safe to, and if the turbo has enough puff.

its not necessary to balance the engine but i got mine balanced when i got it built (for the price i figured i might as well) to +/- 0.05g and the engine feels like it just wants to rev, though it only has a 7400rpm limiter on it at the moment.

[mattis96]

hey mate just out of curiousity, are you gonna assemble the bottom end yourself?

[The Mafia]

hey mate just out of curiousity, are you gonna assemble the bottom end yourself?

Kind of, my mate is a diesel fitter and he's coming over to do it, and I will be assisting.

He's done a couple before, knows what he is doing.

I've since found some bargains:

1. Got a set of ACL duralite Pistons (Stock replacements, but heaps lighter) these are balanced.

2. RB30 rods, Balanced.

The ACL pistons came with rings, should I use these or get better ones? I will have to get the details on them for you all.

[SlipperySil]

1. Got a set of ACL duralite Pistons (Stock replacements, but heaps lighter) these are balanced.

2. RB30 rods, Balanced.

The ACL pistons came with rings, should I use these or get better ones? I will have to get the details on them for you all.

I have heard the ACL pistons are not as good as the stock ones from Nissan maybe be something to check out.

[STATUS]

Kind of, my mate is a diesel fitter and he's coming over to do it, and I will be assisting.

He's done a couple before, knows what he is doing.

I've since found some bargains:

1. Got a set of ACL duralite Pistons (Stock replacements, but heaps lighter) these are balanced.

2. RB30 rods, Balanced.

The ACL pistons came with rings, should I use these or get better ones? I will have to get the details on them for you all.

balancing should be done as a package not individually.

[sky30]

As MBS206 said i would not touch the bottm end, just bolt the head on. Unless your going to bore it and use nissan rings or better, i dont think you will get as good seal as the stock motor/rings.

I had a stocker bottom endwith over 300,000kms on the vl it came from in a r32 it made 312rwkw for couple of years before i decided to build a 4wd forged motor. Trick is to keep revs to 7000rpm or under.

[KwS]

As MBS206 said i would not touch the bottm end, just bolt the head on. Unless your going to bore it and use nissan rings or better, i dont think you will get as good seal as the stock motor/rings.

I had a stocker bottom endwith over 300,000kms on the vl it came from in a r32 it made 312rwkw for couple of years before i decided to build a 4wd forged motor. Trick is to keep revs to 7000rpm or under.

did you freshen the bottom up, with new bearings and rings, or just slap a head on it?

[JonnoHR31]

if you wanna be really right and not buy proper restrictors then you can seal up the standard one (seen a pop rivet used) and drill a smaller one next to it

[MBS206]

did you freshen the bottom up, with new bearings and rings, or just slap a head on it?

I just slapped the head straight onto mine...

[Guilt-Toy]

you should use ACL race series bearings. a set of arp rod bolts and chuck it together with the stock nissan pistons with new standard rings. they are much better then the acl pistons you have mentioned.

balance it as well, rb30's dont like to rev at the best of times so a quick cheap balance will do some good.

as long as you keep detonation away from the engine then it will be fine for over 300rwkw

[Gerg_R31]

straight motors are easy to balance as they are rarely out of balance and if they are its never much. but if they are out of balance, 0.01 grams at 750 rpm can become 0.5grams at 5000rpm or more i forgot the exact maths, but end result bigger vibrations creating unneeded wear and tear

though your list does have pretty much everything thats needed

for a cheap cheap job you could just drill the hole for the tensioner new timing belt, gaskets etc, and whack it all together

though better to use the rb25 pistons and king bearings

if your in sydney send it to my machine shop

Edited November 11, 2009 by Gerg_R31

[KwS]

though better to use the rb25 pistons and king bearings

Doesnt that lower the compression to some stupidly low CR?

Also, i read in another thread that balancing the crank is bad because of something to do with it being nitrided?