Nissan RB30 Engine for Sale | OEM 3.0L SOHC Inline Six

Description

Engine Background

The Nissan RB30 is the 3.0-liter SOHC inline-six produced from 1985 to 1991 for the Australian, New Zealand, South African, and Middle Eastern markets. The engine was developed for the Holden VL Commodore (1986 onward) when Holden needed a six-cylinder that could run on Australian unleaded petrol after the older 3.3-liter Holden six fell behind tightening emission standards. Nissan supplied the RB30 in three variants: RB30S (carbureted, GQ Patrol and some Middle East R31), RB30E (fuel-injected, VL Commodore, Australian R31 Skyline), and RB30ET (fuel-injected and turbocharged, sold ONLY in the VL Commodore Turbo, never in any Nissan production vehicle).

The RB30 architecture is a cast iron block with a 7-bearing forged steel crankshaft, forged steel connecting rods, a crossflow aluminum SOHC head with 12 valves, and a belt-driven camshaft. Bore and stroke is 86 by 85 mm for a total displacement of 2,962 cc. The RB30E and RB30ET use the Nissan ECCS (Electronically Concentrated Control System) fuel injection. The RB30S uses a carburetor. Naturally aspirated variants run 9.0:1 compression. The turbocharged RB30ET runs 7.8:1 compression with stronger internals, an oil pump upgrade, piston cooling oil jets, and a Garrett T3 turbocharger.

Two block series were produced. The Series 1 (S1) block came first in early VL Commodores. The Series 2 (S2) block followed about eleven months later and added provisions on the rear of the block for turbo oil supply, oil return, and a coolant line. Both series can be used for naturally aspirated builds, but turbo and hybrid builds prefer the S2 block for its tapped provisions. RB30ET is always built on the S2 block.

The RB30 is famous in performance circles primarily for the RB30 hybrid stroker build, where the RB30 cast iron block (with its longer stroke than the RB25 or RB26) is mated with the twin-cam DOHC head from the RB25DET or RB26DETT. This combination, known as the RB30DET (or RB26/30 stroker), produces more torque than a stock RB26DETT due to the longer stroke and bigger displacement. RB30 stroker builds have been documented to make 800-plus horsepower with appropriate supporting hardware. A documented used OEM RB30 with verified variant, block series, and compression results is the right starting point for restoration, replacement, or stroker projects.

When Replacement Becomes Necessary

• Excessive oil consumption beyond one quart per 1,500 miles
• Bottom-end knock or rod knock under load
• Loss of compression on one or more cylinders
• Cylinder head warping (the alloy head can warp from overheating, particularly on VL Commodore due to lower radiator placement)
• Cracked head between exhaust valves on overheated units
• Worn timing belt that has been ignored beyond service interval
• Turbocharger shaft play or oil leak (RB30ET only)
• Oil pump failure causing low pressure at high rpm (factory oil pump is the upgrade target on stroker builds)

What to Know Before You Buy

• Variant matters: RB30S (carbureted), RB30E (fuel-injected naturally aspirated), and RB30ET (fuel-injected turbocharged) are three different engines with different compression ratios, induction systems, and supporting hardware. We confirm variant on every order.
• S1 versus S2 block: the Series 2 block has tapped provisions for turbo oil supply, oil return, and a coolant line on the rear of the block. The Series 1 block does not. For naturally aspirated builds, either works. For turbo and stroker builds, S2 is strongly preferred. RB30ET is always S2.
• Donor vehicle matters: VL Commodore RB30E and RB30ET units have a known cracked-head issue from VL-specific cooling system geometry. R31 Skyline RB30E units run cooler and have lower failure rates. GQ Patrol RB30S units are typically work-truck history with high hours.
• RB30 stroker (RB30DET) potential: the RB30 cast iron block plus an RB25DET or RB26DETT DOHC head produces a stroker that outperforms stock RB26DETT in torque. This is the most popular RB30 use case in the modern era. The S2 block with turbo provisions is required.
• Australian regulations and emissions: many RB30S Patrol engines have aftermarket emissions equipment removed. Verify legal status in your jurisdiction before any swap into a US-titled vehicle.

RB30 Variants by Application

Verified variants and donor applications:

What Ships and What Does Not

Direct-Fit and Swap Applications

RB30 Stroker (RB30DET) Build Reference

Not sure if this fits your project? Call us. We verify variant and block series before every order ships.

Search Terms Buyers Use

Used OEM Versus Specialist Rebuild

For an R31 Skyline, VL Commodore, or GQ Patrol restoration, a documented used RB30 with verified variant and compression results is the right starting point. For an RB30DET stroker build targeting 600-plus wheel horsepower, the foundation is the S2 RB30 block with the head and supporting hardware specified per the build plan. RB30DET specialist builds typically run $8,000 to $15,000-plus depending on power target and donor head choice.

Inspection Workflow

• Compression test logged across all 6 cylinders with uniformity reported
• Variant confirmed: RB30S (carbureted), RB30E (fuel-injected NA), or RB30ET (turbocharged)
• Block series identified: S1 or S2 (with turbo provisions tap status documented)
• Donor vehicle disclosed: VL Commodore, R31 Skyline, GQ Patrol, or A31 Cefiro
• Head condition assessed for warping or cracking (VL Commodore cooling history flagged)
• Timing belt service history documented where available
• Turbocharger condition noted on RB30ET applications

Pre-Purchase Buyer Notes

• Specify variant clearly: RB30S, RB30E, or RB30ET are three different engines. State your intended build (NA restoration, turbo restoration, or stroker) so we ship the right unit.
• For stroker builds, insist on S2 block: the tapped provisions for turbo oil and coolant lines are required for any forced-induction build. Skipping this means drilling and tapping the block manually, which is doable but adds machine shop time.
• VL Commodore cooling history matters: many VL RB30E units have head damage from the chassis cooling system. R31 Skyline donors typically run cooler. Disclose donor vehicle on every order.
• Plan a timing belt and water pump at install: the RB30 is a belt-driven engine. Service the belt regardless of donor history, since the cost of a snapped belt on an interference engine is total damage.
• Oil pump upgrade for stroker builds: the factory RB30 oil pump is the most common weak point on high-rpm stroker builds. Plan an aftermarket pump (Tomei, ATI, or similar) at install for any build targeting sustained high rpm.

Why Buy From Part Nests

• Variant confirmed: RB30S, RB30E, or RB30ET documented before payment
• Block series identified: S1 versus S2 with turbo provisions status flagged
• Donor vehicle disclosed: VL Commodore, R31 Skyline, GQ Patrol, or other
• All 6 cylinders compression-tested with uniformity reported
• Head condition assessed for warping or cracking
• No core return required
• Free crated freight delivery to every state
• 15 day replacement warranty against internal defects
• Call us to speak with someone who tracks RB30S versus RB30E versus RB30ET differences, S1 versus S2 block identification, and RB30DET stroker requirements