Do you guys hear a whirling type noise coming from the valvetrain of your X? It kind of sounds like a accessory belt being too tight but comes from the head.

 

Probably the timing chain noise. Belts are definitely quieter.

 

i don't know anything about being smooth as an Evo. I drove a lot of miles in VI - VIII - IX - X
Perhaps they never was stock longer then a week .

 

I am not sure if it's because your an account or not, but your reading comprehension seems to fail you.

I never once compared the 4B11 to a Lexus, BMW or Mercedes Motor. I compared it to a 4g63. In fact I have a stock 4g63 and a stock 4b11 in my drive way to compare to. Do you?

Both vehicles by the way weren't necessarily designed for smooth, quiet operation and both are 4 cylinder turbo high output motors engineered by Mitsubishi. So stop bringing a Lexus into this discussion.

If you get off your "dude why did you by a performance car" trip, and re-read the opening post of this thread, I stated by complaint was with the magazines and Mitsu itself advertising in every publication that they could, that the 4b11 has greatly reduced NVH.

While I could agree that there is less vibration "felt" in the cabin. I cannot agree that there is less noise/vibration overall.

Mitsu has stated themselves that they are trying to target a different audience and possibly divert customers from Audi, Bmw, and Infinity. So I feel I am justified to complain about the motor's noise levels.

Now, with that said, maybe an aftermarket exhaust might mask the sound, I don't know, Maybe you guys wth aftermarket exhausts could tell me.

It's funny that the new improved motor, while seemingly more efficient, seems to be ALOT louder than a STOCK 4g63.

So let’s stop the personal attacks and concentrate on the thread. If you don't agree, that’s fine, don't attack my choices or myself in general.

 

The 4b11 is significantly quieter/smoother than most 4 cyl cars out there. Heck it feels like I'm driving a camry. Until I cruise on the highway and hit anything above 4k rpm. But thats the same for any other 4 cyl revving that high.
After installing an intake and exhaust, I couldn't even hear the engine anymore.

 

I've got to agree that it's not all that quiet especially with the resonance at around 4kRPM.

 

My x has all the right noises. Noises I want to hear...intake sucking air....engine revving....exhaust note...... its a performance 4 cyl. My X has great driver feedback noises.

The x is a step up from previous gen evos for overall noises. The only noise heard under the hood of a stock x is the injectors. The x doesn't have lifters to make the patented mitsu lifter tick sound and the timing chain sound is negligible while driving.

 

Yep, that is what I'm talking about. If it's resonance, I would think there's a way to reduce it.

 

i thought the increased NVH was inevitable when I heard of the increased NVH in the IX - doesn't it have to do with the MIVEC? With MIVEC on both I and E ports in the X. . .

 

The x is way quieter then any car with a 4g in it. Im not saying its lexus quiet or anything but compared to my 1st gens its a world of difference. But it does need another gear bad.

 

Quiter how? Are you referring to interior noise quieter or engine noise quieter. A 1g is not quite an evo....The X's I have been around seem to idle quiet but like the OP said past 4k they are a mechanically loud engine. In stock form at 6000+rpm it almost sounds likes its choked. It does feel that the 4b idle smoother though.