The Nissan VQ35HR is a 3.5-liter naturally aspirated V6 60-degree gasoline engine from the Nissan VQ-family. Nissan’s Iwaki Plant in Fukushima Prefecture manufactures the engine up until this day. Ward’s 10 Best Engines list recognized the VQ35HR engine in 2007.
The Nissan VQ35HR engine is a redesigned version of the previous VQ35DE engine. The lightweight aluminum block with a completely balanced four-bearing crankshaft and two aluminum heads with two camshafts and four valves per cylinder is standard on the VQ35HR.
The Nissan VQ35HR engine features a CVTC system on the intake valves, an e-VTC system on the exhaust valves, and NDIS (Nissan Direct Ignition System) with separate coils on each spark plug. The redline is set at 7,500 rpm.
What are Nissan VQ35HR Engines?
The Nissan VQ series update in 2006 resulted in this 3.5-liter powerhouse engine. Initially, the VQ35HR engine was fitted in rear-drive Nissan and Infinity cars. More than 80% of DE components were redesigned and upgraded to allow the engine to run at high rpm for an extended period of time.
The Nissan VQ35HR engine first appeared in the United States with the release of the redesigned 2007 G35 Sedan model in August 2006. Nissan expanded its VQ lineup with the introduction of the 3.5 L VQ35HR on their lineup.
The engine generates 311 HP for the US market and 306 HP utilizing the updated SAE certified power standard at 6,800 rpm, as well as 268 lb-ft at 4,800 rpm with a compression ratio of 10.6:1.
The Nissan VQ35HR engine is equipped with NDIS (Nissan Direct Ignition System) and CVTC, which are standard for this lineup. Along with that, a hydraulic actuation on the intake cam and electromagnetic actuation on the exhaust cam.
The redline speed is 7,600 rpm. Over 80% of the internal components were reportedly rebuilt or upgraded to withstand an expanded RPM range with a stratospheric 7,600 rpm redline. A new dual-path intake (two air cleaners, throttle bodies, and so on) reduces intake tract resistance by 18%, and new equal-length exhaust manifolds lead to mufflers that are 25% freer-flowing for overall greater airflow.
Engine Specifications and Design:
- Production Run: 2006 – Present
- Cylinder Head Material: Aluminum
- Cylinder Block Material: Aluminum
- Configuration: V6
- Bore: 95.5 mm
- Stroke: 81.4 mm
- Valvetrain: DOHC four valves per cylinder
- Displacement: 3.5 L (3498 cc)
- Compression Ratio: 10.6
- Weight: 290 lbs.
- Maximum HP: 315 HP at 6,800 RPM
- Maximum Torque: 268 lb-ft at 4,800 RPM
Engine Design:
The engine design of the all-new Nissan VQ35HR does not differ much from the DE ones, but it has promising upsides to where the DE does not hold much.
1. Ladder Frame
Crankshaft distortion causes higher vibrations at high rpm. To counteract this, the VQ35HR engine uses a robust ladder frame to support the crankshaft. This increases the engine’s overall stiffness, decreasing vibrations at the high rpm rates at which the
the engine is built.
2. Straight Intake Port
The new VQ35HR has a straight intake port design to assist high-rev, high-power engine performance. This arrangement enhances intake efficiency greatly by supplying the engine with the amount of air necessary during high-speed, high-load engine running.
3. Continuously Variable Valve Timing Control (CVTC)
A valve control system is used in the VQ engine, improving both the intake and exhaust sides where timing is determined through the engine rpm. The system provides considerable flexibility in valve timing operation by utilizing hydraulically activated Continuously Variable valve Timing Control (CVTC) for the intake cams and electromagnetic Valve Timing Control (e-VTC) on the exhaust side. As a result, combustion efficiency is enhanced across the powerband.
4. Optimized Valve Diameter
Although a bigger valve diameter appears to boost airflow, it can actually increase airflow resistance, especially when it is half open, and there is an interfering flow from a neighboring valve. The valve diameter of the VQ35HR has been tuned to decrease intake resistance and promote breathing efficiency over the operational cycle, from low to high valve lift situations.
5. Cylinder Block
The new engine block had the same size and stroke as the previous one, but the connecting rods were extended, and the block deck was elevated by 8.4 mm to lessen piston side-loads.
This improvement, in conjunction with the adoption of bigger crank bearings with main bearing caps strengthened by a robust ladder-type main cap girdle, allows the engine to reliably rev to 7600 rpm. These adjustments provide 6 horsepower by increasing the compression ratio from 10.3:1 to 10.6:1.
Along with that, Nissan wants to minimize friction; that is why the new VQ engine has asymmetrical piston skirts. The diameter of the connecting rod bolt has also been enlarged from 8 mm to 9 mm to gain about 25% in strength.
The crankshaft may flex and twist during high-rev operation, creating noise, vibration, and, perhaps, journal damage. To address this problem, the new VQ35 engine has a bigger journal diameter and a stronger crankshaft. The crankshaft journal diameter has been raised from 60 mm on the DE-engine to 65 mm on the HR version, as has the crankpin diameter from 52 mm to 54 mm.
6. Cylinder Head
The cylinder head of the Nissan VQ35HR is comprised of a robust, lightweight aluminum alloy. As we mentioned above, the engine is equipped with a hydraulically operated CVTC (Continuous Variable Valve Timing Control) for the intake cams and electromagnetic Valve Timing Control (e-VTC) for the exhaust cams.
These two camshafts are propelled by a single primary chain and two secondary chains. The primary timing chain transfers rotational movement from the crankshaft to the intake camshafts, while the secondary chains link the intake and exhaust sprockets on each head.
The new VQ engine uses an asymmetrical dual intake arrangement to minimize air intake resistance. The VQ35HR engine has a straight intake port design to assist high-rev, high-power engine performance. Further, since the VQ35HR engine lacks hydraulic lifters, customized valve lifters are utilized to regulate valve clearance.
Nissan began producing hybrid versions using the Nissan VQ35HR engine and a lithium-ion battery in 2010. This machine has a total power output of 360 HP.
Applications of Nissan VQ35HR Engine:
- 2007 – 2008 Infiniti G35 306 HP
- 2007 – 2008 Nissan Skyline V36 350GT Sedan 308 HP
- 2007 – 2008 Nissan 350Z 313 HP
- 2006 – 2008 Nissan Fuga 350GT 308 HP
- 2008 – 2012 Infiniti EX35 Crossover SUV 297 HP
- 2009 – 2012 Infiniti FX35 Crossover SUV 303 HP
- 2009 – 2010 Infiniti M35 303 HP
- 2011 – 2013 Infiniti M35h 360 HP
- 2010 – Present Nissan Fuga Hybrid 360 HP
- 2012 – 2020 Nissan Cima 360 HP
- 2012 – 2016 Mitsubishi Dignity 360 HP
- 2014 – Present Infiniti Q50 Hybrid 360 HP
- 2014 – 2019 Infiniti Q70 Hybrid 360 HP
Problems Surrounding Nissan VQ35HR Engine:
The Nissan VQ35HR engine is an excellent powerplant with lots of experience too. However, these engines are not exempted from some wear and tear as well as maintenance requirements. Sometimes, some problems or issues might occur.
1. Excessive Oil Consumption
The Nissan VQ35VHR includes a catalytic converter, which is quite sensitive to gasoline quality. They generate ceramic dust, which harms the cylinder sleeve and piston rings. As a result, the engine has poor compression and consumes a lot of gasoline and oil. Such an engine must be repaired or replaced.
However, there are preventable measures to avoid this problem, replace the top catalytic converters with high flow catalytic converters. It will lower the environmental standard, but this problem will not occur.
2. Rough Idling
Rough idling can be caused by different factors. But, in the Nissan VQ35HR engine, the primary reason for this issue is the exhaust camshaft caps. Not only that, but the MAF sensor might also contribute to the overall rough idling of the engine.
Summary
The Nissan VQ35HR engine is one of those engines that can impress you, initially, just by looking at the paper. Its built, power production, and other details say a lot about itself, and don’t count it out as one of the most efficient engines that Nissan made. Overall, the engine is sturdy and solid in comparison to its peers in the industry.
It relies mainly on its capabilities to do its work while being not so expensive. This Nissan’s six-cylinder V-type engine captured the high-performance identity of its previous models and achieved a smoother transition concept above them all.
The new Nissan VQ35HR engine is powerful, agile, and well-suited for front-engine, rear-wheel-drive vehicles.