1968 Mustang Engine Information & Specs – 302 Windsor V8 (4.9 L)

The 302 Windsor V8 Technical Specs & Data

Ford 302 V8

1968 Mustang Engine Information – 302 cubic inch V-8 (4.9 L Windsor V8)

The “Economical” V8 Comes to Mustang

The 302 cubic inch engine was introduced in 1968 to the Mustang, one of seven variations of V-8s were available in the ’69–’73 models. It was designed with Federal emissions regulations in mind. Although it is a derivative of the 289 mustang, some parts are not interchangeable. In fact the block of a 289 cannot be used without some machining. Since the 302 crankshaft is larger, it requires a notched out section in the engine sidewall to allow the connecting rod end bolts to pass. If you are unsure of the parts you are using to build an engine, check tolerances carefully.

Both the engines are 90 degree V8’s. Both are built well and will run forever if you treat them right. I have put well over 500,000 miles on a 302 with minor problems and good maintenance. I have also owned a 1965, 1966 and 1967, 289 CID engine. They all pull strong and have lasted. Good maintenance as with everything is the key.

All 302 engines with the exception of the Tunnel Port and the Boss have 2 bolt mains. The Tunnel port has 4 bolt mains and the 302 Boss has 4 bolt mains and is cross bolted as well. All 302’s drank regular gas except the Tunnel port and Boss engines, they gulped premium gas. Of all the 302 engines, only the Boss had solid adjustable lifters all others had hydraulic lifters.

On the distributor side of the equation, the Boss utilized a dual point, vacuum advance distributor with RPM limits of 5,950-6,050 in 1969 and 6,050-6,150 in 1970. The street 302’s and the Tunnel Port used a single point vacuum advance distributor.

The “J Code” Upgrade

For 1968 only, a special high-performance version of the 302 was offered for the Shelby GT350. The main features included: an angled, high-rise aluminum or iron intake manifold, a larger Holley four-barrel carburetor, and bigger valves of 1.78 in (45 mm) intake and 1.6 in (41 mm) exhaust. It had a longer-duration camshaft, still with hydraulic lifters. The heads had special close-tolerance pushrod holes to guide the pushrods without rail rocker arms or stamped steel guide plates. The combustion chambers also featured a smaller quench design for a higher compression ratio and enhanced flow characteristics. Additionally, high-flow cast exhaust manifolds similar to those on the 289 Hi-Po K-code engine further improved output. Heavy-duty connecting rods with high-strength bolts and a nodular iron crankshaft were also included in this package. Rated power was estimated at 306 hp.

Learn more about the Ford Mustang 302 engine

Engine Basics

Year 1968 “F” Code
bbl 4 barrel
Cylinders 8
Power (hp)
230 hp @ 4,800 RPM
Torque (lb/ft) 300 lb/ft @ 2,600 RPM
Compression 9.0:1
Displacement 302 cu / 4.9 liters
Bore x Stroke 4.00 x 3.00

Year 1968 “J” Code
bbl 4 barrel
Cylinders 8
Power (hp)
306 hp @ 6,00 RPM
Torque (lb/ft) 310 lb/ft @ 2,800 RPM
Compression 10.1:1
Displacement 302 cu / 4.9 liters
Bore x Stroke 4.00 x 3.00

Engine Specs (302 cid V8)

Spark Plugs
Oil filter
Gas Filter
Air Filter
PCV
Oil 5 quarts of 10W30 or 10W40
Oil Pressure 35 – 60 PSI
Points Gap and Dwell at xxx RPM
Timing 6 Degrees BTDC Manual & 6 Degrees BTDC Automatic
Valve adjustment
Valve size
Valve arrangement R. Side I E I E I E I E Front to rear
Valve arrangement L. Side E I E I E I E I Front to rear
Boss 302 Valve Adj. Mechanical Hot lifter adjustment for the Boss 302- 0.025 Intake and Exhaust
Manifold Vacuum 18 inches at idle
Warm Idle Manual Trans 575-600 RPM
Warm Idle Auto Trans 475-500 RPM
Carburetor CFM
Bore and stroke 4.00 X 3.0028
Compression 9.5:1 (155 – 199 psi @ cranking speed), 9.0:1 5.0L
Compression Pressure 130-170 @ cranking speed
HP and Torque 210 or 225 (HO) hp at 4400 RPM and 158 ft/lbs torque at 2400 RPM
Taxable HP 51.2
Distributor Rotation Counter Clockwise
Firing order Non H.O.’s = 1 – 5 – 4 – 2 – 6 – 3 – 7 – 8

Engine 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.

Head bolts 65-70
Crank cap bolts 60-70
Rod end caps 19-24
Intake bolts 20-22
Exhaust manifold bolts 15-20
Upper intake on EFI 12-18
Harmonic damper 70-90
A/C Compressor mounts
Engine fan
Motor mounts to engine 85
Bellhousing bolts
Trans to bellhousing 25
Flywheel to Crankshaft 75-85
Oil pan bolts 7-9
Valve cover bolts 10
Carburetor mount bolts
Oil pickup 10-15
Spark plugs
Oil pump mounting bolts 22-32
Trans. inspection plate
Water pump bolts 15-22
Clutch Pressure plate 35
Water Pump 20
Upper cam gear bolt 40-45
Rocker arm bolts 18-25
Camshaft thrust plate 10

Crankshaft Bearing Journal Specifications

Main Bearing Journal (inches)

Journal Diameter 2.2482 – 2.2490
Oil Clearance
0.0005- 0.0024 Except #1 bearing which is 0.001- 0.0018
Shaft end play 0.004 – 0.008
Thrust on number 3

Connecting Rod Journals

Journal Diameter 2.1228 – 2.1236
Oil Clearance 0.008 – 0.0026
Side clearance 0.010 – 0.020

Piston Ring Specifications

Comp Ring Width

Top 0.077 – 0.078
Bottom 0.077 – 0.078

Ring side clearance

Top 0.002 – 0.004
Bottom 0.002 – 0.004
Oil ring Snug

Ring gap width

Top 0.010 – 0.020
Bottom 0.010 – 0.020
Oil Ring 0.015 – 0.069

Piston Specifications

Code Red 3.9984 – 3.3990
Code Blue 3.9996 – 4.0002
0.003 Oversize 4.0008 – 4.0014
Piston to Cyl. Bore clearance 0.0018 – 0.0026
Piston Pin Bore Dia. 0.9123 – 0.9126

Valve Specifications

Year 1968
Seat angle 45
Face angle 44
Valve spring pressure lbs/inches 180 @ 1.23
Valve spring installed height (in) 1 21/32
Stem guide clearance (in) – Intake 0.0010 – 0.0027
Stem guide clearance (in) – Exhaust 0.0015 – 0.0032
Stem Diameter (in) – Intake 0.3420
Stem Diameter (in) – Exhaust 0.3415

Tune Up Specs

Year Spark Plug Plug Gap Dwell Point Gap Intake Exhaust Carburetor
1968 “J” Code Autolite BF-42 .032″-.036″ 26 – 31 for IMCO, 24 – 29 for Thermactor .017″ for IMCO, .021″ for Themactor 1.773″ – 1.788″ 1.442″ – 1.457″ Autolite 4300 (4V) Automatic choke
1968 Tnl Port Autolite BF-42 2.01″ 1.53″ Autolite 4300-A(2x4V) Auto choke, Holley 4160 (2x4V) manual choke