Honda R20A engine (R20Z)
|Manufacturer||Honda Motor Company
|Also called||Honda R20
|Cylinder block alloy||Aluminum|
4 valves per cylinder
|Piston stroke, mm (inch)||96.9 (3.82)|
|Cylinder bore, mm (inch)||81 (3.19)|
|Displacement||1997 cc (121.9 cu in)
|Power output||110 kW (150 HP) at 6,200 rpm
115 kW (156 HP) at 6,300 rpm
|Torque output||190 Nm (140 lb·ft) at 4,200 rpm
192 Nm (142 lb·ft) at 4,300 rpm
|HP per liter||75
|Weight, kg (lbs)||–
|Fuel consumption, L/100 km (mpg)
|Turbocharger|| Naturally aspirated
|Oil consumption , L/1000 km
(qt. per miles)
|up to 1.0
(1 qt. per 600 miles)
|Recommended engine oil||0W-20
|Engine oil capacity, L (qt.)||4.3 (4.5)
|Oil change interval, km (miles)||5,000-10,000
|Normal engine operating temperature, °C (F)||–|
|Engine lifespan, km (miles)
-No life span loss
|The engine is installed in||Honda Accord
In 2007, they started gradually replacing the K20 for the newer R20A engine, which was created based on the R18A. They took a R18A cylinder block, replaced the crankshaft with a new one with longer stroke (96.9 mm), installed 152.63 mm long rods, the pistons size remained the same, 81 mm, and their compression height was 28.82 mm. This let the old 1.8-liter cylinder block have the displacement of 2.0 liters. The R20A engine also got balance shafts.
The cylinder head was covered by a 16-valve i-VTEC SOHC head. It is similar to the R18A head, but the size of intake valves was increased to 33 mm, of exhaust valves – to 26 mm, and the diameter of valve stem was 5.5 mm.
After every 24,000 miles, valves are to be adjusted, if you hear a noise.
The valve clearances for the cold engine are 0.18-0.22 mm for intake valves, and 0.23-0.27 mm for exhaust valves.
The camshaft is rotated by the timing chain that is incredibly reliable and will never cause problems.
A new 3-stage variable length intake manifold is used here, and the exhaust system uses a more modern catalytic converter.
Comparing the R20A to its predecessor K20A, one may notice that the low/mid range torque increased, fuel consumption decreased, reliability increased, and the engine has become more pleasant for everyday driving. But the sporty nature the K20A was loved for is gone. However, R20A is mainly installed in Honda CR-V, where the dynamics is not the main thing.
Your R20A has two engines with similar design that are also included into Honda R-engines: R16, and R18.
Honda R20 engine modifications and differences
1. R20A1 was the version for Honda CR-V, Acura ILX and Honda Stream. The power was 150 HP @ 6,200 rpm, and the torque was 190 Nm @ 4,200 rpm.
2. R20A2 was another version for Honda CR-V.
3. R20A3 was an analogue to R20A for Honda Accord and Proton Perdana. ECU settings were slightly changed here. The power was 156 HP @ 6,300 rpm, and the torque was 192 Nm @ 4,300 rpm.
4. R20Z1 was the version for Honda Accord 9 gen. and Honda Civic 9th gen. Here the i-VTEC system is able to close half of the intake valves at low rpm. The power was 150 HP @ 6,500 rpm, and the torque was 190 Nm @ 4,300 rpm.
Honda R20A engine problems and malfunctions
This motor is not much different from its 1.8-liter relative called R18A. Their problems are the same, you can learn about them HERE.
But despite some shortcomings, R20A is one of the most reliable engines today.
155 HP is no more enough for you, and you want to add dynamics? Then buy a cold air intake system, an aftermarket header and a performance exhaust system. This will give you up to 170 HP. There is no sense going any further, you have to install a supercharger kit or a turbo kit. We described this method for R18A HERE, it is also suitable for your R20A.