VH45DE Engine Review and All Specs You Need to Know


vh45de engine specs

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Nissan VH motors, released between 1989 and 2001, are available in 4.1L and 4.5L (4,130 cc and 4,494 cc) variations. They comprise a 90-degree V8 with aluminum cylinder block, featuring a closed top deck plus a deep skirt.

Aluminum cylinder heads keep a dual overhead camshaft with four valves construction and pentroof combustion chambers. The production forms and production head castings were applied for many kinds of racing, comprising the IRL.

Nissan VH45DE specs

Manufacturer Yokohama Plant
Also called Nissan VH45
Production 1989-2002
Cylinder block alloy Aluminum
Configuration V8
Valvetrain DOHC
4 valves per cylinder
Piston stroke, mm (inch) 82.7 (3.26)
Cylinder bore, mm (inch) 93 (3.66)
Compression ratio 10.2
Displacement 4494 cc (274.2 cu in)
Power output 207 kW (280 HP) at 6,000 rpm
Torque output 396 Nm (292 lb·ft) at 4,000 rpm
Redline 6,900
HP per liter 62.3
Fuel type Gasoline
Weight, kg (lbs)
Fuel consumption, L/100 km (mpg)
-City
-Highway
-Combined
for Infiniti Q45
16.8 (14)
11.8 (20)
14.7 (16)
Turbocharger  Naturally aspirated
Oil consumption , L/1000 km
(qt. per miles)
up to 1.0
(1 qt. per 600 miles)
Recommended engine oil 5W-30
5W-40
10W-30
10W-40
Engine oil capacity, L (qt.) 5.6 (5.9)
Oil change interval, km (miles) 5,000-10,000
(3,000-6,000)
Normal engine operating temperature, °C (F)
Engine lifespan, km (miles)
-Official information
-Real

400,000+ (250,000)
Tuning, HP
-Max HP
-No life span loss
300+

Applications:

  • Infiniti Q45
  • Nissan President

At the moment of its introduction, VH45DE was rather an innovative motor as a scanty number of V8 motors with double overhead camshafts could boast of great reliability. Actually, the main VH45’s rival in the market was Toyota 1UZ while the other motors with similar characteristics turned out to be non-durable.

The aluminum block and heads of this 90-degree V8 motor contribute to keeping the weight down, which is crucial for maintaining a lightweight vehicle. Each head is provided with 2 camshafts and four valves per cylinder.

The motors, released between 1990 and 1996, kept the brand’s variable valve timing (VTC) and “Coil-on-Plug” ignition system with separate coils for every spark plug. VTC served for increasing the motor output and fuel economy.

Cylinder Block

Keeping an aluminum block with 5-bearing crankshaft supported system, VH45DE features low-friction pistons covered with molybdenum, connecting rods and crankshaft of forged steel, 6-bolt main bearing caps with studs. The diameter of the crankshaft journal is 63.960 mm (2.5181 inches) while one of the crankpins equals to 51.970 mm (2.0461 inches).

While cylinder bore is 93.0 mm (3.66 inches) and the piston stroke is 82.7 mm (3.26 inches), the connecting rods are 147.0 mm (5.79 inches). The compression index equals to 10.2. VH45DE is provided with 2 compression and 1 oil control rings.

Cylinder Head

Light aluminum allows the cylinder head is made of, provides it with great cooling. The motors, produced in 1990-1995, feature the Variable Valve Timing Control system on inlet shafts. VH45DE is supplied with electronic throttle body, exhaust valves filled with sodium, cross-flow cooling system plus hydraulic lash regulators. Single-row silent timing chain controls camshafts.

The diameter of the inlet valve is 38.0 mm (1.47 inches) while the exhaust valve is 33.0 mm (1.2992 inches). Both intake and exhaust duration equals to 248 degrees.

Camshaft Removal

The cylinder head assembly removal and installation should be performed after removing the engine assembly. This section describes the removal of the camshaft, rocker arms and hydraulic lash adjusters.

  • Release fuel pressure. Refer to “Fuel Pressure Release”, “BASIC SERVICE PROCEDURE” in EC section.
  • Remove ornament cover.
  • Remove under cover.
  • Remove radiator.
  • Remove cooling fan.
  • Remove water inlet and outlet.
  • Remove alternator belt.
  • Remove alternator belt idler bracket.
  • Remove air duct.
  • Remove intake manifold collector.
  • Remove intake valve timing control solenoid valve.
  1. Remove left rocker cover.
    a. Remove vacuum pipe.
    b. Remove main harness from bracket and move where it will not
    interfere with camshaft removal.
    c. Remove all ignition coils and spark plugs.
    d. Remove blowby hoses from rocker covers.
    e. Remove rocker cover bolts.
  2. Remove right rocker cover.
    a. Remove power steering oil reservoir tank bolts so tank is
    loose.
    b. Separate fuel pipes.
    c. Remove engine slinger.
    d. Separate blowby hoses from rocker covers.
    e. Remove all ignition coils and spark plugs.
    f. Remove rocker cover bolts.
  3. Remove camshaft.
    a. Set No. 1 piston to TDC on compression stroke.
    b. Remove camshaft position sensor.
    c. Remove front cover upper.
    d. Mark the timing chain links so they correspond to the camshaft
    sprocket and idler sprocket mating marks.
    e. Remove chain tensioner.
    f. Remove camshaft sprocket.Remove camshaft. Loosen and remove the camshaft bolts following the order shown in the figure.
  4. Remove rocker arms.
  5. Remove hydraulic lash adjusters.

Cylinder head distortion

  • Clean surface of cylinder head.
  • Use a reliable straightedge and feeler gauge to check the flatness of cylinder head surface.
  • Check along six positions shown in the figure.
    Head surface flatness:
  • Standard – Less than 0.03 mm (0.0012 in)
  • Limit – 0.1 mm (0.004 in)

If beyond the specified limit, replace it or resurface it.

Compression Pressure

Measurement of Compression Pressure:

  1. Warm up engine.
  2. Turn the ignition switch off.
  3. Release fuel pressure.
  4. Disconnect ignition coil with power transistor harness connectors, then remove ignition coils.
  5. Remove spark plugs.
  6. Attach a compression tester to No. 1 cylinder.
  7. Depress accelerator pedal fully to keep throttle valve wide open.
  8. Crank engine and record highest gauge indication.
  9. Repeat the measurement on each cylinder.
    1,285 /300 – standard.
    991/300 – minimum.
    98/300 – difference limit between cylinders.
  10. If compression in one or more cylinders is low:
    – pour a small amount of engine oil into cylinders through spark plugs holes.
    -retest compression.

 

VH45DE engine problems and reliability

Though VH45DE is noted for its reliability, some troubles still may occur. For instance, the plastic timing chain frequently breaks after 100,000-120,000 miles (150,000-200,000 kilometers) are run. Clearly, a vehicle may drive much more, but it’s important to examine the timing chain regularly. Or, maybe, it’s reasonable to replace it with a metallic one. Also, some problems with MAF-sensor and knock sensors are possible.

Some other faults may happen because of motor aging. Note that the engine will serve longer if to use only good quality fuel and oil as well as maintain it properly.

How to remove the engine?

Situate vehicle on a flat and solid surface. Place chocks at front and back of rear wheels.

  1. Remove transmission.
  2. Remove engine under cover and hood.
  3. Drain coolant.
  4. Drain engine oil from drain plug of oil pan.
  5. Remove vacuum hoses, fuel tubes, wires, harness, and connectors.
  6. Remove front exhaust tubes.
  7. Remove radiator and shroud.
  8. Remove drive belts.
  9. Remove the power steering oil pump.
  10. Discharge refrigerant.
  11. Remove A/C piping.
  12. Install engine slingers to cylinder head.
  13. Set a suitable hoist on engine slinger.
  14. Remove engine mounting bolts.

VH45DE Tuning

If you are fan of high-performance engines and want your VH45DE to reach such a great power as some other V8 motors of the Japanese manufacturers (like Toyota 1UZ, which stock block is able to hold up to 1,000 hp, or Nissan RB lineup, which is highly estimated by many tuning-addicted drivers), we have some good news for you.

Like the brand’s RB series, the VH motors may reach up to 500-600 hp on a fully original bottom end. So, you are free to acquire a far-famed supercharger. Actually, the installment of the supercharger is the most widespread option of adding power to the motor to raise its horsepower to 280 or even 350.

Additionally, the output can be increased with the help of updating OEM camshafts and adapting ECU. Plus, you can acquire performance intake manifold, featuring large throttle body, and high compression pistons. As a result, you will have a chance to achieve more than 400 hp.

Dan Hoffman

Dan is a co-founder of Engineswork. He knows everything about internal combustion engines. Ask your questions in comments down below this article - he will be glad to help you anytime.

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