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hey all,

Building a 25/30 for my track car.

This is what i have at the mo

Rb25 head

Rb30 block

HTA3076R turbo

Trail waste gate

Dump

Screamer

6 Boost Mani

Plazaman Plenum

G4+ link computer

Aeroflow Fuel Rail

1200cc Injectors

BOV

Spitfire coil packs

Fuel set up for E85

So im looking to hoard some more parts

What do you suggest for the, crank, forged rods, forged pistons, oil pump, head studs and sump?

Am i missing anything?

Looking at around 400kws

Edited by Adz2332
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Oil mods. Oil mods. Oil mods..

Baffled/larger sump with a couple of -10an fitting welded onto the sump running to the catch can to help relieve bottom end pressure so the oil can drain back quicker, and so the top end doesnt pump the catch can full.

Drill out the block and head oil drain out. I drilled mine to 10mm to help get the oil down quicker.

Head to sump drain/vent depending if you think its worth it. I dont but some people think its a good idea and acts as a drain. Also could work hand in hand with my first point.

Decent catch can vented or how ever you want to run it.

Will be using my current N1 oil and water pump. WIll be throwing stonger gears into the oil pump before swapping it across.

Restrictors in the block. Work out what you think will be the best size depending on vct, lifters and how you will be using the car.

Im using standard crank, balanced polished and tested.

Ill be ordering forged rods, ARP head studs, main studs

Have cp 86.5mm flat top pistons.

Not sure on my bearings or head gasket yet.

My head will get a full recon. New lifters, valve steam seals, swap my cams across, mods for the vct. GTR cam covers etc. If i didnt really care and was a budjet build id just slam the standard head on and be done with it. Im building this engine up over many years so im not in a rush as im still driving/upgrading the car over the years too.

Thats all i can think of for now. Ill be watching your progress and seeing how its all unfoulding.

Apparently once you let the Nissan out, they are never the same. But ill roll the dice.

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Standard NA bottom end, standard head with wobble sticks if you can afford them.

Enlarged sump with trapdoors/baffles if tracking it. Put 2x -10 fittings on sump regardless.

Take baffles out of cam covers, fill with fuel cell foam and put baffles back on.

Appropriate oil restrictors in block depending on what head you are using.

Then put together and thrash the absolute f**k out of it like I do with mine. HTA3076 should be a killer turbo. If I was you i would go 1.06 rear and really turn up the boost and see how you go. I imagine you should make around 400ish kw depending on a few things.

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Yeah better oil pump, but ARP studs and stuff all good. Doing the same, but slowly. Have RB30 motor, RB25 head with VCT, oil pump, water pump, and gasket set. Next buy is rods I reckon. So also interested in what you are doing, what you get, and how its going.

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Ill be using H beam rods and CP flat top forgies for mine.

SUmp wize im going to get my standard 30 modded with the weld on fittings etc. Not sure if there is any off the shlf items, but i cant say iv looked as im not at that stage yet.

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Oil mods. Oil mods. Oil mods..

Baffled/larger sump with a couple of -10an fitting welded onto the sump running to the catch can to help relieve bottom end pressure so the oil can drain back quicker, and so the top end doesnt pump the catch can full.

Drill out the block and head oil drain out. I drilled mine to 10mm to help get the oil down quicker.

Head to sump drain/vent depending if you think its worth it. I dont but some people think its a good idea and acts as a drain. Also could work hand in hand with my first point.

Decent catch can vented or how ever you want to run it.

Will be using my current N1 oil and water pump. WIll be throwing stonger gears into the oil pump before swapping it across.

Restrictors in the block. Work out what you think will be the best size depending on vct, lifters and how you will be using the car.

Im using standard crank, balanced polished and tested.

Ill be ordering forged rods, ARP head studs, main studs

Have cp 86.5mm flat top pistons.

Not sure on my bearings or head gasket yet.

My head will get a full recon. New lifters, valve steam seals, swap my cams across, mods for the vct. GTR cam covers etc. If i didnt really care and was a budjet build id just slam the standard head on and be done with it. Im building this engine up over many years so im not in a rush as im still driving/upgrading the car over the years too.

Thats all i can think of for now. Ill be watching your progress and seeing how its all unfoulding.

Apparently once you let the Nissan out, they are never the same. But ill roll the dice.

excellent. might have to contact a couple shops here in SA as im not mechanically minded so would either need someone to do the work or get an off the shelf item

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excellent. might have to contact a couple shops here in SA as im not mechanically minded so would either need someone to do the work or get an off the shelf item

RBs have their peculiarities so ask around for a shop familiar with (and expert at) RB engines.

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Limit revs= I found with mine that it was quickest when I shifted at 6250 if I recall right, it kept it in the sweet spot on the torque curve, your build will see a different torque curve so limits will be different, also from my understanding the 30 will be more reliable keeping the rpm down a bit, harmonics or some shit.

Noise limit= some joints don't like screamers due to exceeding their noise restriction limit, plus what is the benefit of a screamer over a plumbed in gate?

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