EK1 1.8L ENGINE

The EK1 1.8l engine was manufactured by Honda Motor Company between 1979-1983 for the 1st generation Honda Accord, 1st generation Honda Prelude, 1st generation Honda Vigor and early 2nd generation Honda Accord models. Introduced new for the 1979 model year, it replaced the standard EF 1.6L in US Accords. It was a water cooled, SOHC 12-Valve CVCC engine with a displacement of 1.8L (1751CC). Output varied as the engine went through two updates during it's production. Most notably was the introduction of the CVCC-II emission setup in late 1980 models. The EK1 1.8l engine was standard in Japanese and US Markets. All other markets worldwide had standard the EL 1.6L engine. Transmission choices were an automatic 2spd/3spd or manual 5 speed.

Overview

• Displacement 1.8 L (1,751 cc)
• Inline four cylinder, transverse
• 77mm bore x 94mm stroke (3.03 in × 3.70 in)
• Cast iron block & aluminum cylinder head
• Three barrel Keihin Carburetor w/ auto choke
• Electronic Ignition
• Belt driven timing gear
• Liquid Cooled - Thermostat controlled fan
• Electric Fuel Pump
• Oil Cooler (or provision on the block)

Engine Block

Cast iron block with integrated water pump insert and large oil passages. Three versions exist (689, PB2 PC1) with additional manufacturing refinements and accessory bolt holes. Blocks are identical for both manual and auto trans per there version.

Specs

• 77mm bore x 94mm stroke (3.03 in × 3.70 in)

Versions

• 689 - Standard layout for 689 cylinder head (79-80 models)
• PB2 -
• PC1 - Oil cooler joint w/ drain bolt added underneath oil filter location (auto). 12mm drain bolt added to front of block for additional coolant drain.

1979 - 1980 CVCC Cylinder Head (689 HF-3)

Six port cylinder head (4 intake ports / 2 exhaust ports) for 1979 and 1980 models.

• Note - 1980 California Automatic models used the newer 1981 cylinder head design only during this year for emission standards.

Specs

• 8:0:1 Compression
• 72 HP @ 4500 RPM
  • 68 HP @ 4500 RPM w/ Hondamatic '79 & '80 Models
• 94 ft lb Torque @ 3000 RPM
  • 94 ft lb Torque @ 3500 RPM w/ Hondamatic '79 Model
  • 94 ft lb Torque @ 2500 RPM w/ Hondamatic '80 Model

Engine Weight w/ Trans

• 5spd - 338.5lbs (153.5kg)
• Auto - 338.7lbs (153.6kg)

Notes

Brand new for 1979 Accord and Prelude models, it essentially was a beefier version of the previously used EF 1.6l cylinder head on a longer block.

1981 CVCC-II Cylinder Head (PB2)

Eight port cylinder head (4 intake ports / 4 exhaust ports) for 1981 models. Introduction of CVCC-II emission system, catalytic converter and EGR valve. Intake valve diameter increased 1mm Dia, Exhaust stayed the same. Exhaust valve ports were doubled spaced to have a greater resistance with uneven heating.

Specs

• 8.8:1 Compression
• 75 HP @ 4500 RPM
  • 68 HP @ 4500 RPM w/ Hondamatic
• 94 ft lb Torque @ 3500 RPM

Engine Weight w/ Trans

• 5spd - 342.8lbs (155.5kg)
• Auto - 392.6lbs (169kg)

Notes

Redesign of the auxiliary valve across all 1981 Honda engine families for the CVCC-II update. Auxiliary chamber was brought closer to the combustion area for more efficient burning. Aux collar features five "torch" holes for mixture burning with a progressive wound spring and thicker valve holder. Piston crowns are dished per the newly updated compression ratio.

1982 - 1983 CVCC-II Cylinder Head (PC1)

Eight port cylinder head (4 intake ports / 4 exhaust ports) with revised intake and exhaust spacing for better heat distribution and exhaust flow.

Specs

• 8.8:1 Compression (9.3:1 debatable per technical bulletin)
• 75 HP @ 4500 RPM
• 96 ft lb Torque @ 3000 RPM

Engine Weight w/ Trans

• 5spd - 351.6lbs (159.5kg)
• Auto - 392.6lbs (169kg)

Notes

The newer cylinder head design created a change in combustion efficiency across the board for all 1982 Honda engine families. The intake and exhaust valve angles were slightly changed and the roof of the combustion chamber is lowered by 1.4mm, raising the compression ratio higher. Exhaust valves are slightly longer, but identical in diameter to the PB2 valves. Intake Valves same as PB2 valves. Piston crowns are deeper dished.