The Honda F-series engine was considered Honda's "big block" SOHC inline four, though lower production DOHC versions of the F-series were built. It features a solid iron or aluminum open deck cast iron sleeved block and aluminum/magnesium cylinder head.
SOHC engines
F18A3 This engine was used in the Rover 618i, assembled in Swindon at the Honda facility.
Specifications Bore × Stroke: Displacement: Cylinder Configuration: Inline-4 Valvetrain: SOHC, 16 valves up to 1997 at 6,000 rpm, at 4,000 rpm carburetor and (PGM-FI-injection, Throttle-body fuel injection) Fuel consumption:
F18B2 This engine was used for the Honda Accord European (model codes CG8 and ) from 1998 to 2002 VTEC S. Japan use variant (F18B) in (model codes CD3 and ) 1.8 VTS/VTE, from 1993 to 2002.
The F18B2 won the 1.8L category of the International Engine of the Year competition for 2000.
Specifications Bore × Stroke: Displacement: F18B2 Cylinder configuration: Inline-4 Valvetrain: SOHC, 16 valves, VTEC + IAB system Compression ratio: 9.3:1 Vtec active at 2,500 rpm IAB active at 4,000 rpm Max power: at 6,100 rpm at 5,000 rpm
F20A This engine series was used in the Accord, Ascot Innova and Prelude in Japan and Europe. The DOHC F20A was also derived from this engine (see below).
Specifications
Bore × Stroke: Displacement: Cylinder configuration: Inline-4 Compression ratio : 9.6:1 Valvetrain: SOHC, 16 valves, non-VTEC Max Power : F20A2 at 5,700 rpm (carbureted) F20A3 at 5,700 rpm (carbureted) F20A4 at 6,000 rpm (PGM-FI) F20A5 at 5,300 rpm (PGM-FI) F20A6 at 6,000 rpm (carbureted) F20A7 at 5,600 rpm (PGM-FI) F20A8 at 5,600 rpm (PGM-FI) Max Torque : F20A2 at 3,500 rpm (carbureted) F20A3 at 3,800 rpm (carbureted) F20A4 at 3,700 rpm (PGM-FI) F20A5 at 5,000 rpm (PGM-FI) F20A6 at 3,500 rpm (carbureted) F20A7 at 4,400 rpm (PGM-FI) F20A8 at 4,800 rpm (PGM-FI) Fuel consumption F20A8 Urban - Highway - Fuel consumption (Japan Combined Cycle): (PGM-FI), (carbureted)
This engine also spawned many variants, according to market, but the specs remain largely similar.
The F20A3 is used in the early carbureted CB3. The F20A5 is used in the CB3 and CB4 Chassis.
F20B3 Used in the Honda Accord Coupe (CD9) (1994-1997) and the Honda Accord Aerodeck (CE2) (Wagon) (1994-1997) Produced for the Netherlands, Belgium, France, Germany, Switzerland and Luxembourg
All the models that came with the F20B3 had a 5 speed manual or 4 speed automatic.
Specifications
Bore × Stroke: Displacement: Valvetrain: SOHC, 16 valves Cylinder configuration: Inline-4 Fuel Delivery: Multi-port fuel injection Compression Ratio: 9.0:1 Max Power: at 5,600 rpm Max Torque: at 4,500 rpm
F20B6 This engine was used for the Honda Accord sold on the European market (model code CG9) from 1998 to 2002
Specifications Bore × Stroke: Displacement: Cylinder configuration: Inline-4 Valvetrain: SOHC, 16 valves, VTEC Compression ratio: 10:1 Vtec active at 4,250 rpm Max power: at 6,000 rpm Max Torque: at 4,800 rpm
F20Z1
This engine series is similar to the F20A above, used in the Honda Accord CC7 (1993-1996) and CE8 (1996-1998) in Europe, as well as the Rover 620i (1993-1999).
Specifications Bore × Stroke: Displacement: Compression Ratio: 9.5:1 Valvetrain: SOHC, 16 valves at 5,400 rpm
F20Z2 This engine is the low compression brother of F20Z1. This engine was used in the same models as the F20Z1.
Specifications Bore × Stroke: Displacement: Compression Ratio: 9.0:1 Valve Configuration: SOHC, 16 valves at 5,300 rpm
F22A This engine series was used in the Honda Accord and Honda Prelude S. Aside from differences in tuning, these engines are substantially similar.
Specifications Bore × Stroke: Displacement: Valve configuration: SOHC, 16 valves, non-VTEC Compression ratio: 8.8:1 Max power: F22A1: at 5,200 rpm. (Accord DX, LX). The 1992–1996 Prelude S also has a F22A1 but because of a different, more aggressively tuned ECU (P12) the power output is . F22A2: at 5,600 rpm. Accord EXi 2WS 1990–1993, Prelude S and SI 1992–1996. 2.2 Lts. water-cooled SOHC with Sequential multi-port fuel injection engine without catalytic converter (KT/KY). Compression Ratio 8.9:1. This engine is equipped with the same camshaft from F22A6 engine, as well as the 4-1 header and simple intake manifold from F22A1 without IABS. Built for the Gulf Market models (Accord and Prelude) this engine is relatively unknown in America. F22A3: European market engine, with more power due to less strict emission standards. F22A4: at 5,200 rpm. (Accord EX) The F22A4 is the same motor as the F22A1 but it has slightly more power due to a tubular designed header and slightly bigger exhaust piping. F22A6: at 5,600 rpm. The F22A6 is the same as the F22A1 except for a slightly more aggressive camshaft, a better flowing cast exhaust manifold, a different more aggressively tuned ECU (PT6), and a different intake manifold that utilizes IAB's and also has a bigger plenum. The F22A6 also has a windage tray in the oil pan, and stiffer valve springs to accommodate the more aggressive camshaft. In cars with an automatic transmission there is an oil cooler present on the back of the block as well. F22A7: European domestic market engine, with more power due to less strict emission standards. (uses PT4, obd1 ecu) .Compression ratio: 9.8:1. F22A9 Australian delivered engine. Similar characteristics to the F22A6 European engine. More aggressive camshaft and slightly larger valves. Standard compression F22A1: at 4,000 rpm F22A4: at 4,000 rpm F22A6: at 4,500 rpm F22A7: at 5,000 rpm
F22B1
This engine was used in the 1994-1997 Honda Accord EX (1993 in JDM Accord models 2.2VTE, VTL & VTS), Indonesian-market post-1996 Accord and the 1997 Acura CL. It was the first F-series engine to feature VTEC.
Specifications Bore × Stroke: Displacement: Piston Length: Compression Ratio: 8.8:1 Rod Length: Rod Diameter: Pin Diameter: Valvetrain: SOHC, 16 valves (4 valves per cylinder), VTEC Max Power: at 5,500 rpm Max Torque: at 4,500 rpm VTEC Switchover: 2300~3200 rpm (depending on manifold pressure) Redline: 6,500 rpm (fuel cut-off action) Firing order: 1-3-4-2 Fuel control: (1994–1995) OBD-I PGM-FI (1996–1998) OBD-II PGM-FI
F22B5
This engine was used in the European Accord known as the Honda Aerodeck.
Specifications Bore × Stroke: Displacement: Piston Length: Compression Ratio: 9.8:1 Rod Length: Rod Diameter: Pin Diameter: Valvetrain: SOHC, 16 valves (4 valves per cylinder) Max Power: at 5,600-5,900 rpm Max Torque: at 4,500-5,000 rpm Redline: 6,200 rpm Firing order: 1-3-4-2 Fuel control: PGM-FI Fuel required: Premium unleaded gasoline (RON) of 95 or higher. (US equivalent of 91 octane)
F22B The F22B2, F22B3, F22B6 and F22B8 are similar, though their exhaust headers vary between each. Found in Honda Accord DX, LX, SE, and Prelude 1993-1997 (F22B2) Honda Accord EXi 1994-1997 (Australia & New Zealand) (F22B3) Honda Odyssey 1995-1997 (F22B6) Honda Shuttle (F22B8)
Specifications Displacement: Bore x Stroke: Valvetrain: SOHC, DOHC Head: SOHC, 16 valves Compression: 8.8:1 Power: at 5,300 rpm Torque: at 4,200 rpm Redline: 6,300 rpm Rev. limit: 6,900 rpm Firing Order: 1-3-4-2 Fuel Control: OBD-I rarely OBD-II PGM-FI
F23A1 This engine was used in the 1998-2002 Honda Accord LX, EX, and SE, LEV models, and in the Acura 2.3CL in North America.
Acceleration 0- for the 4-cylinder models is improved (around the mid-9-second mark), with comparable fuel efficiency to its predecessor: /city and /hwy for LX and EX models with automatic transmissions. Emissions of Non-Methane Organic Gases (NMOG), also known as unburned hydrocarbons, produced during engine warm-up are considerably lower. The LX and EX engines produce less than 0.075 grams per mile, qualifying them for California LEV (Low-Emission Vehicle) status. In California, the Accord EX with the available automatic transmission will produce less than 0.03 grams per mile of NMOG, qualifying it as the first gasoline-powered vehicle to reach ULEV (Ultra-Low Emission Vehicle) status. The five-main bearing block is high-pressure die-cast from aluminum alloy. The walls of the block extend below the centerline of the crankshaft, which helps stiffen the bottom end. FEM (Finite Element Method) computer analysis was used to arrive at optimum thicknesses for the block ribs and walls in order to minimize engine vibration. Additional bottom-end rigidity comes from a larger, stronger bearing-cap beam that ties directly into the cylinder-block skirt. An aluminum-alloy stiffener has been added between the transmission case and the block, just behind the bearing carrier. The stiffener serves to tie the block and transmission together into a single, reinforced unit. FEM was also used to design this stiffener so that it would not only stiffen the area, but also help minimize high-frequency engine vibration. Finite-element analysis of the Accord's piston design by Honda engineers yielded a new ultra-short, lightweight skirt design, which is very rigid and resistant to vibration and piston slap. Like the V-6 engine the pistons are gravity-cast aluminum alloy and utilize full-floating wrist pins in order to minimize noise. The engine's drop-forged single-plane steel crankshaft and connecting rods have been designed to be stronger and operate with less friction, much like the V-6 components. The I-section, drop-forged steel connecting rods have a completely new design and are considerably lighter than their predecessors (475 g vs. 578 g), which helps to minimize vibration. Big end-bearing journal diameter has been reduced from . Rod thickness is down from and the bolt size is smaller. Like the V-6 rod bolts, those of the 4-cylinder engine are torqued to the plastic region of the bolt material in order to ensure a solid union between the bearing cap and the connecting rod. The engine block incorporates the Honda-designed second-order balance system that cancels the inertial forces common to large-displacement 4-cylinder engines. The system consists of a balance shaft on either side of and parallel to the crank-shaft, above its centerline. Driven by a toothed belt, these balance shafts rotate in same directions at twice engine speed. Eccentric weights built into the shafts generate inertial forces that counteract the second-order forces created by the motion of the pistons and connecting rods. This Honda system minimizes vibration in the entire rpm range.
Cylinder Head
The 16-valve, single-overhead-camshaft cylinder head features four valves per cylinder and pentroof combustion chambers. Individual valves are smaller and lighter in 4-valve heads, which allows the engine to be revolved to a higher rpm, helping to extend the engine's power range. Valve actuation is via rocker arms and a hollow, belt-driven single overhead camshaft. The single-over-head-camshaft design requires less under-hood space than the more conventional dual overhead camshafts normally used with 16-valve, 4-cylinder engines. The adoption of a sophisticated knock control system optimizes ignition timing and allows for a higher compression ratio (9.3:1 from 8.8:1). Unleaded regular fuel is specified.
Revised Intake System