The MR20DE (M4R) 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 compression ratio is 10.2: 1. The cylinder bore and piston stroke are 84.0 mm (3.3 in.) And 90.1 mm (3.54 in.), Respectively.
The MR20DE (M4R) engine has an electronic throttle, CVTC valve continuously variable timing system on the intake camshaft, EGR system, and electronic ignition with individual coils on each spark plug.
It produces 133 to 147 PS (98 to 108 kW; 131 to 145 HP) of horsepower and 191-210 Nm (141-155 lbft) of torque.
The engine code breakdown is as follows:
- MISTER – Engine family
- twenty – 2.0 liter displacement
- D – DOHC (double overhead camshaft)
- me – Multi-point fuel injection
|Engine code||MR20DE / M4R|
|Design||Four stroke, Inline-4 (Straight-4)|
|Fuel type||Gasoline (gasoline)|
|Displacement||2.0 L, 1,997 cc (121.68 cu in)|
|Fuel system||Multi-point fuel injection|
133 hp (98 kW, 131 hp) at 5,200 rpm
191 Nm (19.47 kg ·m, 141 lbft) at 4400 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 cylinders in Nissan MR20DE / Renault M4R 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 MR family engines have a connecting rod processed by cracking. These integral casting connecting rods offer a lighter weight than conventional connecting rods, which are built in two parts, separated at the eye where they meet the crankshaft. The cracking processed connecting rod is manufactured in one piece, then the lower connecting rod eye is broken in two (cracking process), and finally the two parts are put back together after assembly. The coupling of the uneven surfaces created by the cracking process results in a very precise bond.
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 coolant distribution system has been thoroughly redesigned in all areas, incorporating it into the block and header.
|Cylinder Block Alloy||Aluminum|
|Compression ratio:||10.2: 1|
|Cylinder bore:||84.0 mm (3.307 inches)|
|Piston stroke:||90.1 mm (3.547 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 to 0.30 mm (0.008 to 0.012 inches)|
|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 …|