1979 Mustang Engine Information – 140 cubic inch I4 (2.8 L Cologne V6)
The 2.8L Cologne V6
The 2.8 liter, 171 ci engine was used in 1979. However, before that it had a previous life as a 171 ci engine. First used in the Mustang II in 1974 to 1978, and then again in 1979 as a 2.8 liter or 2800cc engne. When a person ordered a Mustang, if they got the base model, they always got the 2.3 liter or 140 cubic inch engine. One could upgrade from that point, however, even the best upgrade was meager at best, this was one of the options.
Engine Basics
| Year | 1979 |
| Cylinders | 6 |
| Displacement | 171 cu / 2.8 liters |
| Power (hp) | 90 hp @ 4,200 RPM |
| Torque (lb/ft) | 143 lb/ft @ 2,300 RPM |
| Compression | 8.7:1 |
| Bore x Stroke | 3.660 x 2.700 |
2.8L Cologne V6 Firing Order
- 2.8 liter engine 171 ci V6
- F.O. 1-4-2-5-3-6
- cylinders front to rear RH 1-2-3
- cylinders front to rear LH 4-5-6
- Cylinder compression pressure 101 psi minimum
- Oil pressure at 2000 rpm and warm 40-60
- Spark plugs AWSF42-C @0.034″
- Thermostat starts to open 192-198 degrees
- Thermostat fully open 226 degrees
- Radiator cap pressure
- Cylinder head warp limit 0.003″ in 6″ or 0.006 total
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.
| Intake manifold nuts/bolts (4 steps) | 3-6, 6-11, 11-15, 15-18 |
| front cover plate bolts | 12-15 |
| Front cover bolts | 12-15 |
| Oil pump inlet tube to pump | 7-9 |
| Exhaust manifold bolts | 27-49 |
| Exhaust pipe to manifold bolts | 25-35 |
| flywheel/drive plate bolts | 47-51 |
| oil pan bolts | 7-10 |
| valve cover bolts | 3-5 |
| rocker arm shaft support bolts | 43-49 |
| Main bearing cap bolts | 65-75 |
| Connecting rod cap nuts | 21-25 |
| Fuel pump to block bolts | 12-15 |
| Wheel lug nuts | 80-105 |
| Front hub nut | 17-25, back off then to 10-15 lbs |
| Harmonic damper | 92-103 |
| Bellhousing bolts | 35 |
| Tranny to block | 35 |
| water pump | 20 |
| Engine mount to block bolts | 55 |
| Engine mount to frame nuts & bolts | |
| Carb to intake 2150 2V | |
| Carb to intake model 7200 VV | |
| 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 | 6-10 |
| Spark plugs | 10-15 |
| Oil pan drain Plug | 21-38 |
| Engine block coolant drain plug | 14-18 |
Valve information
| Minimum valve margin width | 1/32″ |
| Intake & exhaust valve seat angle | 45 degrees |
| Intake & exhaust valve face angle | 44 degrees |
| Intake & exhaust valve seat width | 0.060-0.079 |
| Intake & exhaust valve face runout limit | 0.0015″ |
| exhaust valve seat width | 0.070 – 0.090 |
| Intake & exhaust valve seat runout limit | 0.002 |
| Intake stem diameter Standard | 0.3159-0.3167 |
| Intake stem diameter – 0.015 oversized | 0.3566-0.3573 |
| Intake stem diameter – 0.030 oversized | 0.3376-0.3723 |
| Exhaust stem diameter – standard | 0.3149-0.3156 |
| 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 | 0.0008-0.0025 |
| Exhaust valve stem to guide clearance | 0.0018-0.0035 |
| Valve spring out of square limit | 5/16″ |
| Valve spring pressure, standard | 60-68 @1.585″ |
| Valve spring pressure, limit | 10% loss |
| Valve spring free length | 1.91 (about) |
| Valve spring Installed height | 1 37/64-1 39/64 |
| Valve lifter diameter | 0.8736 – 0.8741 |
| Valve lifter to bore clearance | 0.0009 – 0.0024 |
| Service limit | 0.005″ |
Crankshaft Specifications
| Connecting rod journal diameter – Standard | 2..1252-2.1260″ |
| Connecting rod journal out-of-round | 0.0006″ |
| Connecting rod journal taper limit | 0.0006″ per inch |
| Connecting rod Bearing oil clearance desired | 0.0006-0.0016″ |
| Connecting rod Bearing oil clearance allowed | 0.0005-0.0022″ |
| Connecting rod side clearance std. | 0.004-0.0011″ |
| Connecting rod side clearance allowed | 0.014 |
| Main Bearing journal diameter | 2.2433-2.2441″ |
| Main Bearing journal out-of-round limit | 0.0006 |
| Main bearing taper limit | 0.0006″ per inch |
| Main Bearing journal oil clearance desired | 0.0008-0.0015″ |
| Main Bearing journal oil clearance allowed | 0.0008-0.0019″ |
| Crankshaft endplay | 0.004-0.008″ |
| Crankshaft endplay service limit | 0.012″ |
| Cylinder bore diameter | 3.6614-3.6630 |
| Cylinder bore out-ofround limit | 0.005″ |
| Cylinder bore taper limit | 0.010″ |
| Piston diameter coded red | 3.6605-3.6615″ |
| 0.20 oversized | 3.3.6802-3.6812 |
| Piston to bore clearance | 0.001-0.0019″ |
| Piston ring end gap compression rings | 0.015-0.023 |
| Piston ring end gap – oil rings | 0.015-0.055 |
| Piston ring side clearance, compression rings – Standard | 0.0020-0.0033″ |
| Piston ring side clearance service -limit | 0.006 |
| Oil ring | Snug fit |
