Before I even go down this path, let me be upfront in saying I am a big G series fan. I had a 2003.5 BS sedan with the DE motor -- car was totaled (not my fault) on June 20, thanks to 17 year driver, and my sister has a 2010 G37S.

A lot of the rags I've been reading of late, keep making comments about how the VQ37 (and VQ35, for the matter), while torquey and powerful, are seriously lacking in terms of NVH refinement, especially in the upper reaches of the rev band. I've read comments such as:

* The engine in the 370Z is powerful, but sounds and feels like a school bus.
* The VQ engine appears to be close to the end of its development life as the motor lacks the refinement of others in its class.
* The VQ in the M37 is harsh, however, the active noise cancellation does a good job of quelling the NVH of the motor.
* The VQ motor has to be spun hard to obtain its peak power output (relative to its turbocharged competition) and this is where it sounds/feels the harshest.
* The 3.7L motor in the Acura TL, while not as torquey down low, is a far refined motor than the VQ.

etc. etc.

while I never thought the VQ35DE in my 2003 was particularly harsh, I also never felt it was turbine smooth like an inline 6 BMW motor. What are your thoughts on some of this feedback?

Please lets keep the comments constructive. I'm sure everyone here are enthusiasts and love their cars, however, the purpose of forums is to discuss both the good and the not so good.

** NVH=Noise, Vibration, Harshness

 

The VQ was originally designed to be the smoothest possible. This resulted in an excellent engine, that coincidentially also made power.

As such, Nissan decided to pursue power (as made VERY evident by the 3rd and 4th generation VQs), but that came at the cost of increasing revs, as increasing displacement was already out of the question; the 3rd generation VQ has a large bore, and the 4th generation makes more power via revving higher.

It also doesn't help that the VQ has heat issues, which are REALLY exacerbated by the higher redline in the VHR.

The VQ was on Ward's 10 best for the reason that it was versatile, had great output, and most of all, being smooth. It has fallen off as of late because it has lost those properties. Other engines in its class make similar power, often with lower octane requirements, and with similar or better smoothness. The VQ lacks innovation that the other engines in its class have.

 

You bring about a very good question. I am always left wondering what on earth are these reviews talking about. I had an IS250 prior to getting an 08 G, now I am in a '10 G. The IS250 was a silky smooth pathetic week motor. In the G35, I never felt the NVH was anything exceptional vs the IS250. However maybe I have become a fanboy and need to be put in check and Mike's point of view above makes me more interested in what others have to say. One of these days I will test drive the other so called silky smooth motors and see for myself. I suggest you do the same, no amount of words will surpass your own observation

 

Yep. Agree with your assessment. I've read the the 3.0L versions of the early gen VQs were very smooth and torquey (for their time). I know its been a while, but when I drove the 3.0L BMW inline 6, I literally had to watch the tach to get a sense for how hard I was revving the motor in each gear (test drove a manual). It was then that I got a real feel for all the hoopla about the smoothness of a well developed inline 6, relative to a vee configuration.

I had seen some of the nissan PPT presentations prior to the HR version being released and they talked about two things -- (i) the constant "wave of power" (or something to the effect, don't remember exactly, and (ii) the improvement in NVH. I don't get the sense that the NVH improvement between the DE and HR motors is that significant. I think NVH in the 2nd gen G series has been address via external methods like sound dampening, insulation, and now active noise cancellation, more so than the actual source, the motor.

 

A V6 is inherantly unbalanced, because each bank has an uneven number of cylinders, regardless of the angle of the engine, whereas a I6 is balanced.

This is why the I6 Japanese engines of the 90's and the BMW 6's feel so smooth.

 

The VQ35DE/revup had more "instant" power, while the VQ35HR "builds" power. Refer to dynos of the engines, and look at the low end. The DE is punchier.

Infiniti addresses this as "acceleration swell".

Personally, I think the VQ reached its height with the HR. The VQ37VHR is a disaster IMO.

 

I do believe that the VQHR37 is the last of its kind. But dang this engine is so raw in performance, it brings a smile to face every time.

I enjoy the sound of the engine revving, that raw sounds lets you know you got a kick azz engine wanting to push more. And the more it does!

 

We need the RB to make a comeback!

 

I loved the 35HR, but it still wasn't as refined as the older VQ30s (for the masses that is). I personally love the harshness of the HR and VHR.

 

Seriously!!!

You are breaking my heart, LOL.

I really need to check out what you are saying, did not realize I was that much of a fanboy now.

I remember test driving an MDX (Acura engines are also said to be silky smooth) and the motor did not come across as smoother. But then again its no inline 6.

 

couldn't have said it better.

once you hit 4.0 that's into v8 territory.

although a factory turbo/ super charger, should make up for some displacement.

 

if they wouldve put direct injection into the HR i think it wouldve been a total winner. i personally love the rawness of the VQ as opposed to competitors where you get no feeling of where the engine is revving at. the sound at 7k rpm is beautiful IMO, but the engine lacks in innovation. With direct injection we wouldve been looking at an NA motor that makes as much as BMW's twin turbo 6 from the factory.

 

I've never driven the MDX, but my old TL was certainly smoother in the higher rpms than the G.

 

You guys all see Direct Injection as the answer to lacking power, but it is not.

Refer to VW/Audi forums for the problems DI causes. The Toyota (Lexus) 2GR-FSE is the ONLY DI engine to not have buildup issues.

DI can give slightly more power, but it is primarily for efficiency via lean/ultra-lean burns.

 

Harshness is not good; being harsh and having a lot of vibrations leads to faster engine wear.