Nismo Z2 RB26DETT Engine

September 30, 2023

Engine

The heart of the NISMO R34GT-R Z-tune that exhibits such dominating power performance is the RB26DETT Modified Z2 engine. To achieve an engine that generates high power/torque of more than 368 kw (500 ps)/540 N/m (55 kg/m) and provide the high durability required of road-going cars, plenty amount of techniques and know-how that NISMO accumulated throughout the racing scenes, have been lavishly adopted into this Z2 engine, that some may even find the quality to be too much extreme for a road-going vehicle. It is NISMO's qualified mechanics, who has spent many years developing and tuning race engines, who use these high-quality parts and breath life into the engine. The RB26DETT modified Z2, of course has been verified of its performance using cutting-edge equipment such as an engine dyno, and the skills of professional engineers and mechanics. In addition, a serial number is applied to each of the 20 RB26DETT modified Z2 engines, and this will be used for data management in the future.

Engine Model	RB26DETT Modified spec, "Z2" (Z-tune concept engine spec.2)
Engine Type	Water-cooling in-line 6 cylinder DOHC
Bore & Stroke	87mm x 77.7mm
Compression Ratio	8.5 : 1
Displacement	2,771 cc
Max Power	over 368 kw (500ps)
Max Torque	over 540N.m (55kg.m)
	GT Engine Block Since 2001, the 2.8L engine has been used for GT500 competition. It achieves both a 2.8L large bore (ø87 mm) and high boost while maintaining the block rigidity required of an N1 specification engine block with improved strength and rigidity. The engine block used in this Z2 too, is specially made to carry over this GT500 strength and rigidity.
	GT Crankshaft In addition to the GT engine block, a long-stroke crankshaft, which has proven its performance and durability in the GT500 engine and in races of various categories, such as Nürburgring 24-Hour Endurance Race, was used. In addition to achieving a standard ratio 4 mm up long stroke (77.7 mm), die forging and fillet roll machining were used achieve high durability.
	Pistons To achieve the domineering engine performance and engine response of over 368 kw (500 ps)/540 N/m (55 kg/m) at a maximum boost pressure of 0.15 MPa (1.5 kg/cm) using a pistons specially forged for the RB26DETT modified Z2, special lightweight, highly rigid forged pistons with cooling channels were developed.
	GT Connecting Rod As with the GT crankshaft, the 121.5 mm dimension connecting rod has actually been used in the GT500 as well as in vehicles with specifications for the Nürburgring 24-Hour Endurance Race. It is made from SNCM439 to achieve both a light weight and high strength.
	Camshaft The camshaft is an important part that determines the engine performance and characteristics. The major issues facing the RB26DETT modified Z2 engine were balancing the opposing elements of high power and emissions reduction. NISMO resolved these main issues by thoroughly testing the cam profile, lift amount, and valve timing. The optimum values and shapes were used in combination with the selected engine compression ratio, turbocharger, exhaust system, and other components.
	Intake Collector The intake pipe length and diameter as well as the collector tank body cross-sectional shape were changed to improve the airflow to all cylinders and increase the intermediate speed torque.
	Turbocharger A turbocharger made by IHI (though the specifications differ) that has proven itself in both the GT500 since 2001 and in the 2004 Nürburgring 24-Hour Endurance Race is used. Ball bearings are used in the bearings to suppress the drop in the response that is created by large turbochargers while achieving a commanding turbo feeling during high boost.
	Engine Machining : Cylinder head - Combustion chamber shape changed and volume adjusted - Camshaft recess machining - IN &EHX port corrected : Engine block - Boring and honing - Oil gallery plug added : Piston & connecting rod - Weight matching (within 1 g) : Crankshaft - Dynamic balance : Intake collector - Uneven surface correction grinding : Exhaust manifold - Uneven surface correction grinding & stiffener processing
Other parts:
	Intercooler The core capacity was increased, the fin pitch and shape were changed, pressure loss was reduced, and cooling performance was improved.
	Radiator The core capacity was increased, the fin pitch and shape were changed, pressure loss was reduced, and cooling performance was improved. In addition, aluminum was used to focus on cooling performance during high-speed driving and high engine speeds in particular.
	Oil Cooler Twin air-cooled oil coolers were installed on the front side to achieve a stable oil temperature during high-speed driving.
Complete Engine Specification:
Cylinder Head	Camshaft (Z-tune Exclusive)
	Metal Head Gasket
	Special Combustion Chamber shape & Volume Adjustment
	Enlarged Port & Grind machining
	Special Relief Machining on camshaft
	Exclusive Rocker cover with Z-tune special color.
Cylinder Block	GT Engine Block (Strength & Rigidity Uprated)
	Forged Piston (Z-tune exclusive)
	GT Crank Shaft (Forged + Fillet Roll Machining)
	GT Connecting Rod spec 2 ( I Shaped, SNCM Material )
	Oil Pan Baffle Plate
Engine Components	GT Collector Tank (special shape)
	Turbo Charger (made by IHI, Exclusive for Z-tune)
	Exhaust Outlet (special shape)
	Exhaust Manifold specially machined to remove gap & stiffener processing.
Cooling	Twin Oil Cooler (exclusive for Z-tune)
	Aluminum Radiator (Cooling performance upgraded)
	Intercooler (Cooling performance upgraded)
	Intercooler piping
Fueling	High-Flow Fuel Injector
	High-Flow Fuel Pump
Engine Control	ECM (exclusive for Z-tune)
Exhaust	WELDINA NE-1 Titanium (Fr tube is stainless steel)