171 Cologne V6

1974 Mustang Engine Information & Specs – 171 Cologne V6 (2.8 L)

171 Cologne V6 Technical Specs & Data

1974 Mustang Engine Information – 171 cubic inch V6 (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 2800 cc engine. 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 1974
Cylinders 6
Displacement 171 cu / 2.8 liters
Power (hp) 105 hp @ 4,600 RPM
Torque (lb/ft) 140 lb/ft @ 3,200 RPM
Compression 8.2:1
Bore x Stroke 3.660 x 2.700

2.8L Cologne V6 Firing Order

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
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