1988 Mustang Engine Information – 140 cubic inch I4 (2.3 L Lima Inline 4)
The Lima Inline 4 Engine
The 2.3 liter, 140 cid engine was used from 1979 to 1993, it was then dropped from the Mustang line and has not appeared since up to 2014. Prior to being called the 2.3 liter engine, there was a 140 cubic inch engine that magically appeared in 1974 in the Mustang II engine line. It ran from 1974 to 1978 when it was renamed a 2.3 liter engine. Specifications change from year to year, so use the appropriate years engine specs if you are rebuilding or working on an engine.
Engine Basics
| Year | 1988 |
| Cylinders | 4 |
| Displacement | 140 cu / 2.3 liters |
| Power (hp) | 89 hp @ 4,800 RPM |
| Torque (lb/ft) | 120 lb/ft @ 3,000 RPM |
| Compression | 9.0:1 |
| Bore x Stroke | 3.781 x 3.126 |
2.3 liter engine 140 Cubic Inch Firing Order
- 2.3 liter engine 140 ci
- Firing Order: 1-3-4-2
- Cylinders front to rear: 1, 2, 3, 4
- Valve order in head front to rear: I-E-I-E-I-E-I-E
- Cylinder compression pressure: 101 PSI minimum
- 1983 & 1984 Oil pressure at 2500 rpm and warm: 55-60 PSI
- 1985 Oil pressure at 2500 rpm and warm: 40-60 PSI
- Spark plugs: AWSF42-C @0.044″
- Spark plugs turbo model: AWSF32C @0.034″
- Thermostat starts to open: 193-200 degrees
- Thermostat fully open: 221 degrees
- Radiator cap pressure: 16
- Cylinder head warp limit: .007 “
Engine & Other Torque Specifications
All torque specifications provided in this table are those recommended by FORD. If you use special bolts, follow the torque specifications provided by the manufacturer. I recommend that you use the 3 step torque technique where you torque down the bolts in three equal steps. Once you have reached the maximum recommended torque setting, go around one more time. Do not torque in a circular pattern. Always torque cross to cross.
| Cylinder head bolts | 50-60 then 80-90 |
| Flywheel bolts | 56-64 |
| Intake manifold bolts 1979- 1986 | 5-7 then 14-21 |
| Intake manifold bolts 1987-1988 | 15-22 |
| Intake manifold bolts 1989 & on | 20-29 |
| Exhaust manifold bolts 1979- 1986 | 60-84 in lbs, then 16-23 |
| Exhaust manifold bolts 1987 – 1990 | 16-18, then 20-30 |
| Exhaust manifold bolts 1991 on Regular bolts | 15-17, then 20-30 |
| Exhaust manifold bolts 1991 on Stud type bolts | 20-33 |
| Heat shield nuts | 20-29 |
| Oil pan to engine block bolts 1979 – 1986 small bolts | 72-96 in lbs |
| Oil pan to engine block bolts 1979 – 1986 large bolts | 96-120 in-lbs |
| Oil pan to engine block bolts 1987-1990, 1992-1993 | 120-160 in lbs |
| Oil pan to engine block bolts 1991 | 120-144 |
| Oil pan to transmission bolts 1991 | 30-36, then 30-39 |
| Camshaft sprocket bolt | 50-71 |
| Crankshaft pulley to sprocket bolt 1979-1986 | 100-120 |
| Crankshaft pulley to sprocket bolt 1987-1990 | 103-133 |
| Crankshaft pulley to sprocket bolt 1991-1993 | 114-151 |
| Camshaft retaining plate bolt | 6-9 |
| Auxiliary shaft sprocket bolt | 28-40 |
| Timing belt cover bolts | 6-9 |
| Timing belt tensioner adj. screw | 14-21 |
| timing belt tensioner pivot bolt & camshaft cover shield bolt | 28-40 |
| neutral start switch C3 1979-1981 | 12-15 |
| neutral start switch C3 1982 – 1986 | 7-10 |
| neutral start switch C4 | 6-8 |
| neutral start switch C5 | 55-75 “/lbs |
| neutral start switch C3 1982 – 1986 | 84-120 “/lbs |
| neutral start switch AOD | 8-11 lbs |
| Auto transmission pan bolts C3 | 12-17 |
| Auto transmission pan bolts C4 & C5 | 12-16 |
| Auto transmission pan bolts A4LD | 8-10 |
| Auto transmission pan bolts AOD | |
| Engine mount to block bolts 1979 – 1981 | 35-60 |
| Engine mount to block bolts 1982 | 40-55 |
| Engine mount to block bolts 1983-1987 | 33-45 |
| Engine mount to block bolts 1988 on except convert. | 33-45 |
| Engine mount to block bolts 1988 on convertible. | 25-35 |
| Engine mount to frame nuts & bolts 1979-1981 | 40-60 |
| Engine mount to frame nuts & bolts 1982 | 70-90 |
| Engine mount to frame nuts & bolts 1983 | 57-65 |
| Engine mount to frame nuts & bolts 1984 | 50-65 |
| Engine mount to frame nuts & bolts 1985 | 80-106 |
| Engine mount to frame nuts & bolts 1985 turbo bolt | 33-45 |
| Engine mount to frame nuts & bolts 1985 turbo nut | 50-65 |
| Engine mount to frame nuts & bolts 1986 | 45-55 |
| Engine mount to frame nuts & bolts 1987 on bolt | 45-63 |
| Engine mount to frame nuts & bolts 1987 on nut | 80-106 |
| Engine mount to bracket bolts 1985 | 65-85 |
| Carb to intake 2150 2V | 14-16 |
| Carb to intake model 7200 VV | 12-15 |
| Carb to intake 4180-C 4V | 14-20 |
| Driveshaft flange bolts | 70-95 |
| Pedal support brake bracket | 13-25 |
| Clutch self adjuster bolt | 17-26 |
| Wheel lug nuts | 80-105 |
| Front hub nut | 17-25, back off then to 10-15 lbs |
Valve information
| Minimum valve margin width | 1/32″ |
| Intake & exhaust valve seat angle | 45 degrees |
| Intake & exhaust valve face angle | 44 degrees |
| Intake valve seat width | 0.060-0.080 |
| Intake & exhaust valve face runout limit | 0.0016″ |
| exhaust valve seat width | 0.070 – 0.090 |
| Intake & exhaust valve seat runout limit | 0.003 |
| Intake stem diameter Standard | 0.3416-0.3423 |
| Intake stem diameter – 0.015 oversized | 0.3566-0.3573 |
| Intake stem diameter – 0.030 oversized | 0.3376-0.3723 |
| Exhaust stem diameter – standard | 0.3411-0.3418 |
| Exhaust stem diameter – 0.015 oversized | 0.3561-0.3568 |
| Exhaust stem diameter – 0.030 oversized | 0.3711-0.3718 |
| Intake valve stem to guide clearance | 0.0010-0.0027 |
| Exhaust valve stem to guide clearance | 0.0015-0.0032 |
| Int % Exh valve stem to guide clearance svc. limit | 0.0055 |
| Valve spring out of square limit | 5/16″ |
| 1984 & up Valve spring pressure, valve open | 71-79 lbs @ 1.52″ |
| 1983-on Valve spring pressure, service limit | 5% loss” |
| Installed height | 1 17/32 – 1 19/32 |
| Hydraulic valve lash adjuster diameter | 0.8422 – 0.8427 |
| Hydraulic valve lash clearance in borer | 0.0007 – 0.0027 |
| Service limit | 0.005″ |
Crankshaft Specifications
| Connecting rod journal diameter 1983-on | 2.0465-2.0472″ |
| Connecting rod journal out-of-round | 0.0006″ |
| Connecting rod journal taper limit | 0.0006″ |
| Connecting rod Bearing oil clearance desired | 0.0008-0.0015″ |
| Connecting rod Bearing oil clearance allowed | 0.0008-0.0026″ |
| Connecting rod side clearance std. | 0.0035-0.0105″ |
| Connecting rod side clearance allowed | 0.014 |
| Main Bearing journal diameter 1979 – 1990 | 2.399-2.3982″ |
| Main Bearing journal taper limit | 0.0006″ |
| Main Bearing journal runout limit 1979 – 1990 | 2.399-2.3982 |
| Main bearing taper limit | 0.0006″ per inch |
| Main Bearing journal runout limit 1979-1990 | 0.005″ |
| Main Bearing journal oil clearance desired | 0.0008-0.0015″ |
| Main Bearing journal oil clearance allowed | 0.0008-0.0026″ |
| Crankshaft endplay | 0.004-0.008″ |
| Crankshaft endplay service limit | 0.012″ |
| Cylinder bore diameter | 3.7795″ |
| Cylinder bore out-of-round limit | 0.005″ |
| Cylinder bore taper limit | 0.010″ |
| 1979 Piston diameter coded red | 3.7780-3.7786″ |
| 1979 Piston diameter coded blue | 3.7792-37798″ |
| 1983-1990 piston to bore clearance limit | 0.0033-0.0038″ |
| Piston ring end gap compression rings 1979-1991 top & bottom | 0.010-0.020″ |
| Piston ring end gap oil ring | 0.015-0.055″ |
| Piston ring side clearance, compression rings 1979-1990 std. | 0.002-0.004″ |
| Piston ring side clearance service limit | 0.006″ |
| Oil ring | snug fit |
