The Nissan S13 240SX is one of the most beloved rear-drive platforms of the late 20th century, and swapping in a built RB30DET has become the gold standard for enthusiasts chasing four-digit power potential. While the original article scratched the surface, the reality of building a 600+ horsepower S13 with an RB30DET involves far deeper engineering, meticulous part selection, and real-world testing. This article dives into the details of what it actually takes to push an RB30DET past the 600 hp mark, including chassis preparation, drivetrain upgrades, tuning nuances, and the hard lessons learned by successful builders.

Why the RB30DET? The Hybrid Powerhouse That Defined an Era

The RB30DET isn’t a factory Nissan engine—it’s a hybrid. Builders take the 3.0‑liter RB30 block (originally from the Nissan Patrol or Skyline GTS) and mate it with an RB26DETT cylinder head from the legendary GT‑R. The result is a 3.0‑liter inline‑six with the head flow and turbo architecture of the RB26. This combination yields a massive displacement advantage over the 2.6‑liter RB26 without sacrificing rev-happiness.

  • Displacement: 3.0 liters vs. 2.6 liters (RB26)
  • Stroke: Longer stroke provides more torque down low
  • Head: RB26DETT’s four‑valve per cylinder design and robust oiling
  • Turbo Options: Single or twin; most 600+ hp builds use a single large frame turbo

This engine combination has been proven in countless street cars, drift machines, and time attack builds. Compared to an RB26, the RB30DET offers an extra 400cc of displacement, which means it spools turbos earlier and makes more power per pound of boost. For a target of 600 hp, the RB30DET can achieve this on moderate boost levels (20–25 psi) with a properly sized turbo, whereas a 2.6L would need more aggressive boost and risk detonation.

Chassis Preparation: The S13’s Weak Spots at 600+ HP

The S13 chassis is light and nimble, but it wasn’t designed for 600 wheel horsepower. Before any power is added, the body and suspension need to be addressed. Ignoring these areas results in axle tramp, chassis flex, and excessive tire spin that make the car dangerous and slow.

Reinforcement and Stiffening

  • Seam welding: Weld the chassis seams in the engine bay, transmission tunnel, and rear subframe mounting points.
  • Strut braces: Front and rear strut braces reduce chassis twist.
  • Roll cage or half cage: Required for serious track work and adds significant rigidity.

Suspension and Brakes

  • Coilovers: 600+ hp needs proper damping control. Look for high‑end units from KW, Ohlins, or competition-grade brands.
  • Adjustable arms: Rear camber arms, toe rods, and traction arms are essential to keep the tires planted.
  • Brakes: Stock S13 brakes are inadequate. A Z32 (300ZX) brake swap or aftermarket big brake kit with slotted rotors and race pads is a must.
  • Solid subframe bushings: Replace worn rubber with polyurethane or solid bushings to stop wheel hop.

Drivetrain Upgrades

Transmission: The stock S13 transmission will shatter at 600 hp. Popular options include the CD009 from a Nissan 350Z (with an adapter plate) or a built RB25 transmission. Many builders choose a Tremec T56 or a Hollinger sequential gearbox for serious competition use.

Clutch and Flywheel: A twin‑plate clutch setup (e.g., OS Giken, Exedy Hyper Twin) is necessary to hold the torque without slipping or damaging the input shaft.

Differential: The stock open diff must be replaced with a limited‑slip unit. A welded diff works for drifting, but a 2‑way LSD from KAAZ or Cusco offers better control everywhere. Upgrade the axles to Stage 2 or Stage 3 units if using sticky tires.

Critical Engine Modifications for 600+ HP

Building an RB30DET to reliably output 600 wheel horsepower requires more than just a bigger turbo. The internals must be forged, the oiling system must be improved, and every component needs to be matched to the power goal.

Short Block Assembly

  • Pistons: CP‑Carillo or JE forged pistons with a compression ratio of 8.5:1 to 9.0:1.
  • Rods: Manley H‑beam or Carrillo Pro‑H beam rods rated for 900+ hp.
  • Crank: The stock RB30 crank is strong, but a knife‑edge or aftermarket billet crank adds reliability at high RPM.
  • Bearings: ACL Race or King bearings with proper oil clearances.
  • ARP hardware: Main studs and head studs are mandatory.

Cylinder Head

  • Porting: A mild port and polish focused on the exhaust side improves flow.
  • Valves: Oversized stainless or inconel valves for high‑boost durability.
  • Springs and retainers: Aftermarket valve springs to prevent float above 7,000 rpm.
  • Cams: Aftermarket camshafts from Kelford or Tomei with around 270° duration and 10mm lift.

Forced Induction

For 600 wheel horsepower, a single turbo is the most common choice. The Garrett GTX3582R or Precision 6266 are proven. The turbo should be mounted with a quality cast manifold (e.g., from Full Race) to avoid cracking. A 44mm or 50mm wastegate (Tial) is required for boost control. An external blow‑off valve, such as a Tial Q50, keeps the compressor wheel safe between shifts.

Fuel System

  • Injectors: ID1700 or FIC 1650 cc/min injectors (for use with E85).
  • Fuel pump: Single or twin in‑tank pumps (Walbro 525 or Aeromotive 340).
  • Fuel lines: −6AN feed and −6AN return, plus a fuel pressure regulator (FPR) set to 43.5 psi base pressure.
  • Fuel type: E85 is highly recommended for 600+ hp to prevent knock and allow more ignition timing.

Cooling Systems

  • Radiator: A high‑flow aluminum radiator with dual 12‑inch fans.
  • Oil cooler: A 19‑row or 25‑row Setrab oil cooler with a thermostat.
  • Intercooler: A front‑mount core at least 4 inches thick (e.g., 600×300×100mm).
  • Water injection: Some builds use water‑meth injection for added safety.

Engine Management

A standalone ECU is non‑negotiable. The Haltech Nexus R5, Motec M150, or Link ECU are popular choices. They allow full control over fueling, ignition timing, boost control, and safety features (knock monitoring, cylinder trims). The car should be tuned on a dyno by a professional who specializes in RB engines. Expect to spend 10–15 hours on tuning alone.

Tuning Strategy: Making Safe, Repeatable Power

A 600‑horsepower RB30DET that is “just fast” isn’t impressive if it detonates or overheats. The tuning process needs to focus on reliability. The base fuel map should be set to 11.5:1 air‑fuel ratio under boost (12.2:1 for E85). Ignition timing is typically 15–18 degrees of timing at peak boost (25 psi) tapering to 12 degrees at redline.

Boost control should use a gear‑based strategy. For example, lower boost in first and second gears to maintain traction, then full boost in third through fifth. A boost controller like the Haltech Dual Solenoid module or a standalone EBC is highly effective.

A real‑world example: RIPS (Rotary Intake and Performance Systems) in New Zealand has produced numerous 600+ hp RB30DET S13s. Their builds often use a Garrett GTX3582R at 22 psi on E85, producing 620 wheel horsepower and 580 lb‑ft of torque. Their tuning targets include a conservative ignition curve and meticulous fuel pressure logging.

Driving Experience: How 600 HP Feels in an S13

With 600 wheel horsepower in a 2,700‑pound chassis, the S13 transforms into a monster. Throttle modulation becomes critical: too much gas in second gear will light the tires instantly. A well‑set up suspension and sticky 275‑section semi‑slicks are required to plant the power. At highway speeds, the RB30DET pulls like a freight train, with the torque beginning around 3,500 rpm and building aggressively to 7,000 rpm.

Drivers often report that the car feels fast on the street, but “scary fast” on the track. The chassis becomes nervous under hard braking, and the rear end tries to step out even in third gear corners. A good limited‑slip differential and careful steering input are essential.

Common Pitfalls and How to Avoid Them

  • Oil starvation: The RB30 block has oiling issues under high G‑load. Install a baffled oil pan and an Accusump pre‑oiler.
  • Knock at high boost: Always tune on quality fuel (E85 or race gas) and install an aftermarket knock sensor.
  • Overheating: An aluminum radiator is not enough. Add an oil cooler, a performance thermostat, and consider a higher flow water pump.
  • Clutch slip: Use a twin‑disc setup—single disc clutches won’t hold 600 hp for long.
  • Axle failure: Upgraded axles from The Driveshaft Shop are a must if you run drag radials.

Budget Considerations: What Does It Really Cost?

A basic 600‑horsepower RB30DET S13 build can easily exceed $40,000 parts and labor not including the cost of the car. Here’s a rough breakdown:

  • Engine short block build: $6,000–$10,000
  • Head work and cams: $3,000–$5,000
  • Turbo, manifold, wastegate, exhaust: $4,000–$6,000
  • Fuel system (pumps, injectors, lines, rail): $2,000–$3,500
  • Intercooler and piping: $1,500–$2,500
  • ECU and tuning: $3,000–$5,000
  • Transmission and clutch: $4,000–$8,000
  • Suspension and brakes: $5,000–$8,000
  • Labor (swap, fabrication, wiring): $6,000–$12,000

Total estimated cost: $35,000–$55,000. This is why many builders choose to buy a complete built car rather than start from scratch. However, performing the work yourself can cut the cost by one‑third.

Reliability at 600+ HP: Can It Be a Daily Driver?

With the right build and conservative tune, a 600‑wheel‑horsepower RB30DET S13 can be driven on the street—but it will never feel like a factory car. Heat soak in slow traffic, heavy clutch pedal, and stiff suspension are realities. Many owners keep their 600‑hp S13 as a weekend toy or track car and run a second vehicle for daily duty. If you must daily drive it, invest in proper heat management (hood vents, larger radiator) and consider a quieter exhaust to avoid police attention.

For reference, Haltech’s tuning guides recommend using boost control tables to limit power in first and second gear to preserve drivetrains. This approach extends the life of the differential and axles significantly.

Final Thoughts: The Real Reward

Building a 600‑horsepower RB30DET S13 240SX is not just about a dyno number. It’s about the engineering challenge, the thrill of a perfectly tuned inline‑six, and the satisfaction of owning a vehicle that can hold its own against modern supercars. The RB30DET’s combination of displacement and high‑revving head makes it uniquely capable. But it demands respect: proper maintenance, quality parts, and a builder who understands the limitations of a 30‑year‑old chassis.

Whether you’re building for grip, drift, or straight‑line speed, the S13 RB30DET platform offers a genuinely rewarding experience—provided you are willing to spend the time, money, and effort. For more detailed build guides, check out the GKTech articles on chassis reinforcement, or the technical forum discussions on RB30 swaps.