The MR18DE engine features a lightweight aluminum block with a fully balanced five-bearing crankshaft and an aluminum cylinder head with two overhead camshafts (DOHC) and four valves per cylinder.
The cylinder bore is 84.0 mm (3.3 in) and the piston stroke is 81.1 mm (3.19 in). The compression ratio is 9.9: 1. The Nissan MR18DE engine has an electronic throttle, CVTC valve continuously variable timing system on the intake camshaft, EGR system and NDIS (Nissan Direct Ignition System) with individual coils on each spark plug.
It produces 124 to 128 PS (91 to 94 kW; 122 to 126 HP) of horsepower and 173-176 Nm (17.6-17.9 kg ·m, 127-130 lb ·ft) of torque.
The engine code breakdown is as follows:
- MISTER – Engine family
- 18 – 1.8 liter displacement
- D – DOHC (double overhead camshaft)
- me – Multi-point fuel injection
|Design||Four stroke, Inline-4 (Straight-4)|
|Fuel type||Gasoline (gasoline)|
|Displacement||1.8 liters, 1,797 cm3 (109.65 cubic inches)|
|Fuel system||Multi-point fuel injection|
124 PS (91 kW; 122 HP) @ 5200 rpm
173 Nm (17.6 kg ·m, 127 lb ·ft) at 4,800 rpm
|Order to open fire||1-3-4-2|
|Dimensions (L x W x H):||–|
The engines in the MR family use the same technology as in the HR series. The MR18DE has an aluminum cylinder block with a five bearing crankshaft support system. The cylinders in Nissan MR18DE engines are positioned in an offset to minimize friction that arises from the connecting rod angle when a piston descends into the cylinder. The resulting smoother reciprocating motion of the pistons contributes to high power output and high torque, as well as fuel economy. In addition, the structure is designed so that the piston remains in the upper part of the cylinder longer than in a conventional engine (the speed of the piston decreases). This enables more efficient use of combustion energy and effectively improves thermal efficiency.
The crankshaft and camshaft journals are finished with a polishing tape to produce a mirror-like finish. The result is a total reduction in friction on these bearing surfaces of key engine components. The cylinder bore is 84.0 mm (3.3 inches) and the piston stroke is 81.1 mm (3.19 inches) and the compression ratio is 9.9: 1. The Nissan Engine MR18DE has two compression rings and one oil control ring.
|Cylinder Block Alloy||Aluminum|
|Compression ratio:||9.9: 1|
|Cylinder bore:||84.0 mm (3.307 inches)|
|Piston stroke:||81.1 mm (3.193 inches)|
|Number of piston rings (compression / oil):||2/1|
|Number of main bearings:||5|
|Cylinder bore (standard):||84.000-84.010 mm (3.3071-3.3075 inches)|
|Piston Skirt Diameter (Standard):||83.970-83.980 mm (3.3059-3.3063 inches)|
|Piston Pin Outside Diameter:||19.989-19.995 mm (0.7870-0.7872 inches)|
|Piston ring side clearance:||Top||0.040-0.080 mm (0.0016-0.0031 inch)|
|Second||0.030-0.070 mm (0.0012-0.0028 inch)|
|Petroleum||0.015-0.185 mm (0.001-0.007 inches)|
|Piston Ring End Gap:||Top||0.20-0.30 mm (0.008-0.012 inch)|
|Second||0.50-0.65 mm (0.020-0.026 inch)|
|Petroleum||0.15-0.45 mm (0.006-0.018 inch)|
|Connecting rod bushing inner diameter:||20.000-20.012 mm (0.7874-0.7879 inches)|
|Connecting Rod Big End Diameter:||47.000-47.001 mm (1.8504-1.8504 inches)|
|Connecting rod center distance:||143.44-143.54 mm (5.647-5.650 inches)|
|Diameter of main crankshaft journal:||51.979 mm (2.0464 inches)|
|Crankpin diameter:||43.970 mm (1.7311 inches)|
|Crankshaft Center Distance:||40.41-40.49 mm (1.5909-1.5940 inches)|
The cylinder head is made of a light and strong aluminum alloy, which gives it good cooling efficiency. Each camshaft is supported by five bearings. The MR18DE has a Continuously Variable Valve Timing (C-VTC) system on the intake camshaft. C-VTC enables variable valve timing in response to engine rpm …