2005 Mustang Engine Information & Specs – 281 Modular V8 (4.6 L)

Modular 4.6L SOHC V8 Technical Specs & Data

2005 mustang 4.6 v8

2005 Mustang Engine Information – 281 cubic inch V-8 (4.6 L Ford Modular V8)

Ford’s Modular 4.6L SOHC V8

While the modular V-8 still displaced 4.6 liters, the engine block was now cast out of lighter aluminum rather than iron; saving 75-pounds and featured a deep skirt for added strength. Inside the block was a set of short skirt aluminum pistons with an antifriction coating and wrapped with high-tension piston rings for longer life and better oil control. Once again, the cracked-powdered-metal connecting rods were used after proving their durability in past modular motor Mustangs.

Bolted to the top of the aluminum block was a pair of new cylinder heads that were taken from the 5.4-litre Triton truck engine. These aluminum three valve-per-cylinder heads allowed the engine to breath better at high engine speeds since they allowed the incoming air a more direct, port-style path to the two intake valves. The new heads allowed engineers to raise the compression ratio to 9.8:1 while still being able to safely run on regular grade fuel. Operating the valves was the camshaft lifted directly from the 5.4 Triton engine along with another innovation that was a first for any Mustang; Variable Camshaft Timing.

Variable Camshaft Timing (VCT) allows for better engine performance, increased fuel efficiency and reduced emissions by electronically adjusting the camshaft timing. The system works by directing high pressure oil through electronically controlled hydraulic valves into the camshaft phaser cavity. When the Powertrain Control Module (PCM) requires a change in cam timing, depending on factors such as engine load and RPM, it will send a signal to the hydraulic valves to regulate oil flow to the phaser cavity. This in turn causes the camshaft to rotate slightly from its initial orientation thus resulting in the camshaft timing being advanced or retarded depending on the needs of the PCM. Since the Mustang employed a single overhead cam design the VCT system operated both the intake and exhaust valves simultaneously.

Crowning the improved V-8 was an all new intake system featuring an intake manifold with tuned runners. At the end of these runners was another new feature to the Mustang called a charge motion valve. These flaps would close at light loads and low engine speeds causing the air entering the engine to speed up and induce a tumble effect in the combustion chamber allowing fuel and air to mix more thoroughly and burn efficiently. When the driver put their foot down on the accelerator and engine speeds rose or when under heavy loads these flaps would then open fully allowing maximum air flow into the combustion chamber. Throttle control on the V-8 was controlled electronically just as it was with the 4.0-litre V-6.

Year 2005
VIN Code H
Cylinders 8
Displacement 281 cu / 4.6 liters
Power (hp) 300 hp @ 5,750 RPM
Torque (lb/ft) 320 lb/ft @ 4,500 RPM
Compression 9.8:1
Type 3V

Engine Specs

Spark Plugs PZT1F, Set gap to 0.040 – 0.5. inch torque to 25lbs
Valve arrangement Per cylinder is 2 intake and 1 exhaust
Fuel 87 octane
Compression 9.8 : 1
HP and Torque Horsepower 300 @ 5750 rpm / Torque 320 lb-ft@4500 rpm
Taxable HP
Firing order 1-3-7-2-6-5-4-8
Lobe lift intake and exhaust 0.217
Allowable lobe lift loss 0.005
Endplay 0.0002 to 0.0090
Journal diameter 1.126 – 1.127
Bearing inside diameter 1.128 – 1.129
Journal to bearing oil clearance 0.001 to 0.003 (0.002 inch maximum)
Oil 6 quarts of SAE 5W20
Antifreeze 13.6 quarts – use yellow colored only DO NOT MIX COLORS!

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 or pattern specified by FORD. Many specs are given in inch pounds. 12 inch pounds is equal to 1 foot pound. The use of a inch pound torque wrench is desirable because it is more accurate at most lower settings.

Flywheel/ drive plate bolts 59
Flywheel driveplate bolts In 2 steps; 10 lbs, then 52 lbs
Front jackshaft sprocket bolts
Step 1 = 33 lbs, step 2 + 90 degrees
Rear jackshaft sprocket bolts
Step 1 = 15 lbs, step 2 + 90 degrees
Jackshaft chain tensioner bolts 80 inch lbs
Jackshaft chain guide bolts 168 inch lbs
Jackshaft thrust plate bolts 90 inch lbs
Engine mount nuts 46
Engine mount bracket to engine block bolts 41
Engine mount to chassis 41
Upper cam gear bolt
Subframe mounting bolts 85 lbs
Crank cap bolts
Valve cover bolts 89 in lbs
Accessory brackets 35
oil pan bolts 18 in lb, 15 lbs, + 60 degrees
Oil filter adaptor bolts 18 lbs
Oil pump to engine block 89 inch lbs
Oil pickup screen to to engine block bolt 18 lbs
Ol pickup tube to oil pump bolts 89 inch lbs
rear main seal retainer 89 inch lbs
timing chain cover bolts
15 lbs, then an additional 90 degrees
timing chain stationary guide bolts 89 inch lbs
Timing chain tensioner bolts 18 lbs
valve cover bolts 89 inch lbs
crankshaft pulley bolt
66, step Loosen 1 turn, step 3 = 37 lbs, step 4 = tighten an additional 90 degrees