The Nissan VQ35HR vs. Nissan VQ37VHR. The Nissan 350Z and Infiniti G35 were the first vehicles to use the VQ35DE 3.5L V6 engine. Nissan introduced the VQ35HR engine in 2007 for the 350Z and G35’s final years. In 2009, the VQ37VHR 3.7L V6 was introduced for the newer 370Z and G37 models. Despite sharing the same VQ engine family, these engines have significant differences. In this guide, we compare the VQ35HR and VQ37VHR engines, including specifications, performance, and reliability.
VQ Engine Family by Nissan
Nissan VQ engines are available in a variety of years and models. They began manufacturing in 1994, and VQ engines are still used in some models as of 2023. The VQ engines are all built on the same general V6, aluminum, DOHC platform. Displacement, on the other hand, ranges from 2.0L to the 4.0L VQ40DE.
Of course, the VQ engines in general aren’t our primary focus here. We’re comparing the Nissan VQ35HR to the VQ37VHR. To tie everything together, we’ll also include some information for the older VQ35DE engines. After that, let’s go over some of the fundamentals of these three VQ engines.
VQ35DE 3.5 V6
Again, the original VQ35DE is not the focus of this article. When comparing the VQ35HR vs VQ37VHR engines, it does help to tie everything together. In any case, the VQ35 first appeared in the 2002 Nissan Altima. It will be available in the following years for the 350Z and G35:
- Nissan 350Z model years 2003-2006
- G35 Infiniti 2003-2006
The standard VQ35 engine produces 287 horsepower and 274 pound-feet of torque. In 2005, a Rev-Up variant with 298hp and 268 lb-ft of torque was introduced. Only certain models have this engine, and the difference is a redline of 7,000 vs. 6,500.
The VQ35HR engine
Nissan took the VQ35 to the next level with the introduction of the VQ35HR engine. It is a 3.5L V6 with the same basic design; the engine block and a few other things remain the same. The HR variant, on the other hand, uses approximately 80% newly designed parts, making it a very different engine. It occurs in the Z and G35 years:
- Nissan 350Z model years 2007-2008
- G35 Infiniti 2007-2008
HR stands for high-revving, and this VQ35HR delivers with a redline of 7,500 RPM. Compression is increased to 10.6:1 along with numerous internal engine updates to accommodate the increased revs. Overall, the VQ35HR is designed to be more powerful, fuel efficient, and environmentally friendly than the previous engine.
The Nissan VQ37VHR
The use of a 3.7L V6 engine is a significant change between the 370Z and G37. The numbers in the engine code represent displacement, if you haven’t guessed by now. The same is represented by the car badging. In any case, Nissan increased the displacement of this engine. The VQ37VHR can be found in the following locations:
- 370Z Nissan 2009-2020
- G37 Infiniti 2008-2013
This engine has approximately 65% of the same parts as the previous VQ35HR engine. Only about one-third of the parts are new, so it isn’t as significant an update as the VQ35HR vs VQ35DE. It’s an interesting fact given the larger displacement, which necessitates the addition of quite a few new parts.
HR versus VHR
More details will be discussed in the sections that follow the engine specs. We just want to clear up a few points here. The VQ37HR engine does not exist, and the VQ37VHR is the only engine in the VHR family. The V in the name stands for Nissan VVEL technology, and this is the company’s first production engine to use it.
As with the VQ35HR, HR stands for high-revving. In other words, the addition of the VVEL system on the VQ37VHR is the primary difference.
VQ35HR vs VQ37VHR Specifications
The following are the specifications for the Nissan VQ35HR vs VQ37VHR engines:
As you can see, many of the specifications are very similar. The VQ37 has a larger displacement and different valve timing systems. The larger VQ37VHR, of course, has more power. Although the torque increase is minor, the Nissan VHR engines have a much better power curve. There is more torque available in the low and mid ranges. Let’s compare more VQ35HR vs VQ37VHR specifications below.
VQ Engine Components
The aluminum engine block is shared by all of the engines discussed in this article. Despite the fact that the VQ37 has a larger engine. Nissan simply increased the displacement to 86mm by increasing the piston stroke. The bore size remains unchanged at 95.5mm.
Internals of the VQ35HR and VQ37VHR
The longer stroke and higher compression account for the majority of the internal engine differences between the VQ35HR and VQ37VHR. Shorter connecting rods and new piston designs were required for the VQ35. In the grand scheme of things, these changes are insignificant.
Some believe the internals of the VQ37VHR are slightly stronger, while others believe they are roughly equal. It’s something to think about if you want to go with boost or other high-powered mods. But that’s a different topic for another day.
Valvetrain VQ35 vs VQ37
We briefly mentioned above that the VQ37VHR torque curve is much better, despite having only a few more peak torque. The VVEL system is a major contributor to this. The VQ35HR uses dual VVT, which is still excellent technology.
The VHR’s VVEL system, on the other hand, is more advanced and allows for far more valve and timing control. It is comparable to BMW’s Valvetronic systems. Overall, these systems provide a great power-band while also being extremely efficient and emitting low levels of pollution. It’s a nice addition to the VQ37VHR engine.
Other VQ Distinctions
Of course, this does not include all of the updates and changes. Another significant improvement for the VQ37HR was the intake manifold design. It employs shorter runners to improve top-end power output. Short runners aren’t usually ideal if you want good torque at low revs. However, Nissan most likely chose this route because the VVEL can offset those losses and then some. Dual intakes are also used in VHR engines.
We could go into more detail, but this covers the majority of the important updates. Remember that the VQ35HR and VQ37VHR are more closely related than the VQ35DE. This is true even after changes to displacement, valve control, and so on.
Reliability of Nissan VQ35HR vs VQ37VHR
There isn’t much to say about the 350/370Z and G35/37’s dependability. That’s great news. However, all cars and engines have their share of problems. No internal combustion engine is perfect, and the VQ35 vs VQ37 is no exception. However, there is no perfect answer as to which is superior.
We wrote an article about Nissan VQ37VHR problems here, as well as a guide to VQ35DE engine problems. For their stock power output, both engines are quite robust and well-built. On either engine, major engine problems or reliability issues aren’t a major concern.
Is the Nissan VQ35HR more dependable than the VQ37VHR? We honestly don’t have a perfect answer, and much of it is situational. A lot of it comes down to luck of the draw and upkeep. If these engines are well maintained, they should provide very similar reliability.
There are a few other factors to consider before purchasing a VQ35HR vs VQ37VHR engine. Of course, price and model are important considerations. The VQ35HR in the 350Z and G35 is a bit older, so they’re typically less expensive to buy. When comparing a 2008 350Z VQ35HR to a 2009 370Z VQ37VHR, the price difference isn’t significant.
When comparing a 2018 370Z to a 2007 350Z, price differences can become significant. Most likely, you’re not looking at the extremes. However, if you want to avoid a vehicle that is more than ten years old, the VQ37VHR is the best option. Some are even under warranty, as the Z was manufactured until 2020.
VQ Engine Mileage & Age
To return to the reliability discussion, a newer engine will generally provide better reliability. In the short to medium term, at least. As a result, the VQ37VHR is most likely the more dependable engine. Again, the difference isn’t significant when comparing vehicles with similar years and mileage.
Which Is Better: VQ35 or VQ37?
Both Nissan engines are capable all-around performers. They provide an excellent balance of performance, dependability, and fuel economy. It’s also fair to say that they’re both significant improvements over the older VQ35DE engine. Anyway, which is better, the VQ35HR or the VQ37VHR?
We believe the VHR engine is superior. It’s more recent, has a slightly larger displacement, and employs Nissan’s VVEL variable valve timing system. That’s not to say the VQ35HR is a bad engine in any way. For many owners, one engine isn’t significantly better than the other, but the 3.7L VHR has a slight advantage.