To heed the indirect call of one of their fiercest competitor in the late 80s and 90s, Toyota did not hold back to answer such queries, and they are up to the challenge hence the creation of the VZ engines.
VZ engines are designed for truck and SUV applications, but Toyota took the risk and integrated it into smaller vehicles. And one of those engines that took a trip and experienced it all from bigger vehicles to smaller ones is the Toyota 3VZ-FE engine. And today, we will talk about is engine design, applications, issues, reliability, the overall impact on the industry, and many more.
What are Toyota 3VZ-FE engines?
The Toyota 3VZ-FE engine is a naturally-aspirated, V6, water-cooled, internal combustion engine manufactured by Toyota Motor Corporation from 1987 to 1997. The 3VZ FE engine is a member of the VZ family of machines and is a response to Nissan’s VG engine. This engine family introduced many changes for Toyota, such as electronic fuel injection system, ECU, and engine improvements throughout the years.
VZ engines are well-suited for various applications as they perform best in low to mid-level torque and power range.
In addition, the VZ engine block is made from robust cast-iron material with two-bolt bearing caps and large interconnected main bearing cradles. It has forged steel crankshafts and cast iron main bearing support girdles installed and standard in this 3VZ-FE engine.
It also features two aluminum heads with two camshafts and acts with four valves per cylinder. The 3VZ-FE engine is equipped with an electronic ignition system with a mechanical distributor and Sequential Multi-port Fuel Injection System (SFI);
Engine Specifications and Design:
- Production Run: 1987 – 2007
- Cylinder Block Material: Cast-iron
- Cylinder Head Material: Aluminum
- Configuration: V6
- Bore: 87.4 mm
- Stroke: 82 mm
- Valvetrain: DOHC with four valves per cylinder
- Displacement: 3.0 L (2958 cc)
- Compression Ratio: 9.6
- Weight: 439 lbs.
- Max HP: 185 HP at 5,800 RPM
- Max Torque: 189 lb-ft at 4,600 RPM
The engine architecture of the 3VZ-FE engine happens to be a physically tall machine; since it was initially made for SUV and pickup truck use. To fit it on FWD engine bays, Toyota tilted the engine towards the firewall. This tilt, approximately 15 degrees that are almost reaching the rear cylinder bank, is impossible to locate without removing the intake manifold.
The 3VZ-FE does not have much with the rest of the VZ engine family in terms of the engine parts. Cams are interchangeable between the 3VZ-FE and 5VZ-FE.
The 3VZ-FE engine block is made from strongly made cast-iron material. It has six cylinders arranged in V orientation at a bank angle of 60-degrees and a deck height of 223 mm. The engine’s firing order is 1-2-3-4-5-6. The crankshaft is then supported by four main bearings, made from copper and lead alloy, inside the case, and it is integrated with nine semi-counterweight for an added balance.
Oil holes are drilled in the crankshaft center for the oil supply to the pistons, connecting rods, and other internal components.
The 3VZ-FE engine has a bore size of 87.4 mm, a stroke length of 82 mm, and a 9.6 compression ratio; its crankpin diameter is 55 mm, and the crankshaft primary journal diameter is 64 mm.
The pistons are made from high temperature-resistant aluminum material. Into the piston head, a depression is built to prevent the interference of the piston with the valves—full-floating type piston pins with the pins fastened to neither the connecting rods nor the piston boss.
Each of the pistons is equipped with one oil control ring and two compression rings, where the compression rings are split into two materials, with one ring made from steel and the second ring is made from cast iron. The oil ring, however, is made from a combination of both stainless steel and pure steel.
Each piston ring’s outside diameter is made to be slightly larger than the piston’s diameter, and the flexibility of the rings creates a cylinder wall hub when they are mounted on the piston.
The 3VZ-FE cylinder heads are made from aluminum with a cross-flow type intake and exhaust layout. The engine spark plugs are located in the center of the pentroof-type combustion chamber, allowing better leverage to burn the fuel inside. It has a belt-driven double overhead camshafts design with four valves per cylinder – two for both intake and exhaust valves.
The intake camshafts are driven through a single timing belt that engages to a gear on the exhaust camshaft connected from the intake camshaft gear to drive it. Between the valve lifters of each cylinder and the front end of the cylinder head, the camshaft journal is supported at four exhaust and five intake places.
The intake valves of the 3VZ-FE engine are 34 mm in diameter, while the exhaust valves have a 27.3 mm diameter. The valve lift is 7.85 mm, the intake duration is 230 degrees, and the exhaust duration is 230 degrees. The exhaust and intake valves are installed with irregular pitch springs made from a special valve spring carbon spring that can function highly depending on the engine speed demand.
Valve clearance adjustments are made through an external shim type system, in which these valve adjusting shims are situated on top of the valve lifters. This allows a better angle when replacing the shims because you will no longer have to remove the camshafts.
The 3VZ-FE was used in the North American market only in 1992 and 1993 for the Camry platform, while New Zealand and Australia saw it from 1992 to 1996. It became available in some parts of Asia in the Toyota Windom up until May 1997. After 1994, Toyota replaced the 3VZ-FE with 1MZ-FE engines in most vehicles; but it is still widely used in Australia until 1996, especially for the Camry.
The power range of the 3VZ-FE engine is stretched to reach the maximum torque between 2,500 – 4,600 RPM, with power trailing off by 6,000 RPM. The stock redline sits at 6,600 RPM.
The 1992 – 1993 engine version was rated 185 HP up to 197 HP at 5,800 RPM and a torque range of 188.7 lb-ft to 203 lb-ft.
Some applications of the 3VZ-FE engine:
- 1992 – 1993 Toyota Camry (USA)
- 1992 – 1996 Toyota Camry (Australia and Europe)
- 1992 – 1996 Toyota Windom
- 1992 – 1993 Lexus ES300 (USA)
- 1993 – 1996 Toyota Scepter (Japan)
- 1993 Toyota Hilux
Engine Tuning, Upgrades, and Modifications
The 3VZ-FE engine is already powerful, even in stock form. With its capacity, there is no contest that this engine will come straight at you bursting. But, if you want to increase your engine’s power, that is possible too; and the best choice for that power increase is head porting.
The first thing is to service it for port and polish; if you can do it yourself and knowledgeable about it, go. Then, buy some performance parts such as headers, cold air intake, and a 2.5-inch performance exhaust system. Install all these upgrades and configure the ECU; this can give you around 200 HP. Throw in some other performance cams with 262/262-degree lift, and gain an extra 15 HP.
You can extend the horsepower to 250 by buying or swapping it with a more powerful one. In some cases, you can buy a 1MZ TRD supercharger kit and modify it to fit in the 3VZ. Another option is to build a turbo kit using turbochargers used in Supras, make turbo manifolds, and do everything custom.
When tuning your engine, avoid increasing the compression ratio, buying an aftermarket intake manifold, lighter pistons, and other parts. It is costly, and the power return would not mean much.
Problems Surrounding 3VZ-FE Engines
The Toyota 3VZ-FE engine, despite being a highly reliable and durable engine, still has its weaknesses and shortcomings, like the other machines. They are not exempted from some issues that might affect the performance, motor, and system. That is the reason we created a preventive list reminder for those who wanted or already owned a 3VZ-FE engine. Though some issues here do not affect all the machines, it is still best to have a piece of prior knowledge on their problems firsthand.
The first and the most common problem of the 3VZ-FE engine is engine overheating. The primary culprit of overheating is the loss of coolant supply in the machine. We all know that oil deprivation can cause severe damage to the engine and affects the performance throughout. Check first your coolant level, and if it is on a low level, the problem is in the head gasket; there might be a leak; if the level is normal, check the cooling fan because it often fails. After you’ve checked everything and none of those appeared to be the reason, check the radiator cap, radiator condition, and the thermostat; it might be there.
Another 3VZ-FE issue that needs to be tackled is engine knocking. These foreign sounds haunting because it sounds like a game over for this engine but try to adjust the valve clearances, and if that solves the knocking, you’re good to go. If not, bring it to a specialist to check what is wrong with the engine.
Other 3VZ-FE problems include an increase in the wear of the connecting rods, and sometimes cylinder head cracks occur.
3VZ-FE engines are old enough to be victims of excessive oil consumption, apart from what we’ve mentioned earlier due to loose components and deteriorating parts. Use the recommend high-quality engine oil and avoid compromising for this part. Have the engine serviced regularly and constantly monitor the condition of the cooling system.
As a newer and modified version of the 3VZ-E engine, a successor to the 2VZ-FE, this engine is a flexible tool for those who wanted SUV power installed in a smaller vehicle. It is equipped with solid materials and delivers the adequate capacity to satisfy your driving experience. It features some technologies that became the staple system in the Toyota brand. Though it has some issues regarding its engine overheating, connecting rods, and even its age, this engine is still thriving as solid as a rock. Many people still sought for this engine as they are a good platform for tuning and other upgrades. With the proper maintenance and regular inspection, this engine can last and surpass the 200,000-mile mark.
I hope that this simple guide and discussion helped you understand the 3VZ-FE engine’s design, applications, abilities, issues, tuning potential, aftermarket support, reliability, and overall impact on the industry and community.