Andrew's R32 Gtr With Forged Rb30Dett Build

[gtr fan]

I didn't really port them as such - I really just matched the turbo flange to the turbo's (ie removed the lip on the manifold). All up maybe 15 minutes per manifold?

When I bolt them up to my new cylinder head, I will have to match up the actual runners to the exhaust ports, which will take much longer, but will post up details when done.

I was wrong, they did it for $60 in total, which I was happy about.

Great article in Autospeed!

[dorifticon]

So, I have acquired a separate sump and transfer case for building the rb30 long-motor.

I decided to run with the tomei gated sump baffle.

As the name suggests, it has a series of gates surrounding the oil pickup to keep it immersed in the oil and prevent oil starvation under high cornering loads/launches/braking.

The instructions specify that the existing drillings in the sump (which are basically pinholes) need to be drilled out to 5mm. This requires some dissassembly of the sump assy to get the drill in there, in particular removing the passenger-side driveshaft oil seal and removing the driveshaft and pipe.

Edited January 4, 2010 by dorifticon

[dorifticon]

Here is a shot of the drillings opened up. Obviously stuff rags into to the driveshaft openings, don't want swarft going all through the bearings and diff.

And then give it a real good hosing to get rid of any swarf.

Here's the baffles installed - I put a dab of high-temp loctite on all the bolts, don't want anything working it's way loose down there!

[dorifticon]

The RB30 blocked back from machining - cleaned, crack tested, decked, bored/honed and tunnel bored.

It has also been drilled and tapped to run 12mm studs, and the timing belt tensioner has been relocated.

Edited March 30, 2010 by dorifticon

[dorifticon]

I am running a nitto high-flow oil pump, as well as forged nitto rods. I was particularly keen to run forgies given the extra side loads created by the increased rod length and angles, and since the motor is going to be seeing fairly serious boost. These particular rods have a special provision in the side to spray oil onto the thrust side of the bores. Hopefully this will offset any effects of not running piston oil squirters.

[dorifticon]

The obligatory forged slugs - these will maintain the standardish (for the rb26 twin cam head) static compression ration around 8.5:1. Also the machined crank. It's been balanced, as well as the galleries sized and micropolished. Being an RB30 crank, I of course had the wider oil pump drive collar pressed on. Hopefully, in combination with the nitto pump, I will be able to maintain strong oil pressure. The clearances are slightly higher to run a heavier oil.

Edited March 30, 2010 by dorifticon

[GT-R32]

Wow, great stuff Andrew. It's going to be an animal.

[dorifticon]

Getting the damn engine out was a mission and a half. We reviewed all the hints and tips on the net, but really accessing those two top bolts for the motor seemed impossible without moving the engine/motor assembly forward. We ended up taking off the front turbo (was a lot easier since it had been off not long ago, and we retapped/antisiezed the studs and nuts) as well as the power steering, A/c, and alternator. Then we ripped the engine mounts out of the car completely (secured the motor with a crane). We also undid the gearbox mounts and both prop shafts, and let it rock down slightly. We slid the motor forward to undo the top 2 bolts, then secured the gearbox in place with a trolley jack (we were still able to angle the front upwards).

Once the starter motor was out, we undid the rest of the bolts and slid the motor forward and out. It was a time-consuming task and I broke one engine mount in the process, but she came out in the end. If I could have done anything differently, though, I would have removed the engine pulley, just to get a bit more clearance between the radiator support/Aircon condenser - once the prop shaft was out we couldn't stop the motor from turning over.

So now the r32 sits, waiting for a new heart...

[dorifticon]

Wow, great stuff Andrew. It's going to be an animal.

Thanks mate, I hope so. It's had budget blowouts that would make SOCOG proud, but as we all know that first time you drive it, when it's all run in, and just floor it and hit boost...

makes you forget about the gaping hole in the wallet.

[dorifticon]

Well, it's been slow going, mainly due to delays getting the balancer and timing belt, but the work has been progressing.

One of the tricky issues was spacing the engine down to get sufficient bonnet clearance for the taller motor. Here is a pic of the steel spacer plates I and a mate made up to sit between the rail and the k-frame. I may do a more detailed write-up with the dimensions etc once the install is finished.

Also I ended up going with a (good condition) second hand HKS triple plate clutch - should hold the extra power better than the OEM one that was in there.

[dorifticon]

Even after the major issues have been tackled, there are still a multitude of annoying little things that need to be sorted. Here is a list of them:

-Timing belt cover - even using the rb30 lower timing belt cover leaves a 38mm gap. I will probably tack weld on a bit of sheet to bridge the gap.

-twin turbo support brackets - there is no provision for the alloy braces that sit below the turbos (mounted off the dumps). Haven't figured out how I will address this yet.

-new oil drains required off turbos - for the additional block height and also because a t-piece is needed to run 2 oil drains into one block mounting boss. Also if you are running an oil drain from the back of the cylinder head (not an issue unique to rb30's but anyway) a further t-peice is required.

-New oil and water feeds for the turbos are required as the stock ones won't bend far enough. I got braided lines from ebay (big props to eiji takada!)

-knock sensor mounts - there is provision for 2 knock sensors but the mounts are different thread diametre and pitch to the ones on the rb26. An adapter is required.

-the rear oil drain needs to clear the hard vaccuum and water lines at the back of the head. I "modified" (hacksawed) the bracket on the driver's side.

-the rb26 power steering bracket needs to be modified. You CANNOT use the rb30 one, it is different (I tried).

-the rb26 cast iron exhaust flanges need to be ground back to clear the rb30 block (assuming you didn't mod the block)

-there are a couple of heater hoses and the diff brether hose that needs to be replaced on the driver's side due to the extra distance between the plenum and the bottom of the motor

-the crank bolt and washer from the rb26 doesn't fit the 30 - an rb30 one is required.

All in all it's a lot more screwing around than I realised. The problem is you don't really know there's a problem until you attempt to install x to y and realise you need z. Then there's delay getting the part, which all kills the motivation really, especially when you're working after hours and weekends on the thing.

Had I known at the outset, I really would have built a 2.8 stroker with the 2.6 block. Oh well, live and learn.

[dorifticon]

So there were some more screw-ups along the way.

This picture illustrates the problem getting the intercooler plumbing to line up, and then the solution - just inserted a section of 3" pipe with a bead welded on and some hose clamps. Same solution for both sides of the engine bay. There's also a long piece of rubber or silicone pipe required for the bov connections.

Edited July 30, 2010 by dorifticon

[dorifticon]

Even with the engine dummy installed in the car (ie the long motor) and ensuring the timing belt cover doesn't foul on the bonnet, that's not the end of the problems. The twin-turbo pipe also fouls. This may be why many of the GTR rb30 conversions seem to also have a single turbo conversion, with custom pipework. The solution was to grind off the boss for the "twin turbo" sticker and then took up the rest with washers in the rear bonnet hinges. It aint pretty but it works. Kinda.

[dorifticon]

So, with everything in place, the engine was filled with running-in oil (penrite 15-40 running in oil) and we set about trying to get oil pressure. There was a bit of screwing around trying to get oil into the oil cooler lines, filling the filter, etc, but eventually after cranking it for a while with the plugs out and the injectors unplugged, the oil pressure started to creep up.

Between the sump adapter, the bone dry engine and the oil cooler lines I reckon it took around 8 litres.

Once we fired it up the oil pressure really came up and it just kind of idled along. It was a bit rumbly with the 272 deg cams and the zorst off, but it idled well considering it's not tuned at all for this setup.

[dorifticon]

Ah crap.

The y-pipe off the twin dumps doesn't fit up - the extra deck height has moved the cylinder head up 30mm or so (once the spacer is accounted for) and the bottom of the exhaust fouls on the passenger footwell.

So it needs to be trailered to an exhaust shop to mod the y-pipe before it can be tuned.

One bloody headache after another.

[paulR32gtr]

No good - people were not joking telling me the change in deck height causes major headaches!

Looking good though and getting close - will be worth it in the end.

[dorifticon]

No good - people were not joking telling me the change in deck height causes major headaches!

Looking good though and getting close - will be worth it in the end.

Gees I hope so.

Front pipes were modified at fyshwick exhaust and then trailered over to ESP for run-in tune.

With 12psi boost and fairly low revs, and timing pulled out higher in rev range it makes 244 kw. The turbos will be the main bottleneck at this point, but hopefully the HKS 2530s should still be capable of taking it well into the 300's.

Initial impressions of driving it is that it is very responsive - the turbos come on from nearly no revs at all. I thought the 272 deg cams might make it doughy but if anything its more punchy.

The clutch shudder in 1st at takeoff is an issue though - Glen reckons we might have damaged the clutch plates when installing the engine, but after reading a few posts on here it might be that it just needs bedding in (clinging to the faint hope that I won't have to fork out $$$ to have gearbox dropped and clutch rebuilt/replaced...).

Oh well I'm not going to focus on the negative. We've achieved a lot just getting the rb30 conversion on the road so if we have damaged the clutch I will chalk it up to experience and move on. Hopfully it can punch out a decent number in the end.

[Gtir-keiron]

Awsome write up mate,Theres 2 fairly inteligent guys who do work on my car where i live and both of them always say,The millions of dollars the japs spent on

R n D to get things where they should be,Not often they got things wrong.

Can i ask a simple question,I love the whole 26/30 deal,I have 2 mates with that very setup in rear wheel drive cars.

But!!

Has any one ever put a rb30 block and a rb26 block naked on the scales?

People might be very supprised.

25/30 turbos are the best street twins on the market for a gtr id stick with me bud i love mine.

[dorifticon]

25/30 turbos are the best street twins on the market for a gtr id stick with me bud i love mine.

Hey thanks for the kind words.

I agree the HKS2530's are super-reponsive - especially in a slightly cammy rb30 - however I didn't fork out $$ for a balanced and forged rb30 to run mid-300's (not that there's anything wrong with that!).

With the recent developments in turbos and a good tubular manifold (I am currently running OEM cast iron, lightly ported) I can probably get big increases in power without sacrificing much, if any, drivability.

As far as the weight goes, I can't think of a simple way to weigh the two blocks. Even then I don't know how much it would tell you, because there is all the other crap like sump adapters and bolts, clutch, brackets etc that would add up. Also although the rb26 is shorter it has more ribbing etc so it may not work out to be hugely different.

[GTScotT]

I agree the HKS2530's are super-reponsive - especially in a slightly cammy rb30 - however I didn't fork out $ for a balanced and forged rb30 to run mid-300's (not that there's anything wrong with that!).

Not to break your heart, but 2530s (aka 2860 -5s) are good for 450rwkw.

The last member I spoke to who hit the 450 and couldnt go further due to limitations of his intank fuel pumps. This was with garrett -5s too, not the more expensive HKS branded item.

Then again you could be aiming for 600rwkw, I wouldnt know .