That's not a 991.2 problem. That's just a specific car problem.

 

is this tapping sound normal on an engine with less than 4000 km?

 

My 2017 . 2 Kicks, barks and makes weird sounds every morning. Great reason to be alive!!!!

 

Yes, I thought this was problem with only my car but when dealer service manager tells me this is quite common that make it 991.2 problem.

 

Does it make lifter tapping noise though?

 

Keep in mind your base 991.1 does not have PASM, while a base 991.2 does. If you are the kind of person who prefers dumb suspensions (I think I am), that could influence the driving impression further.

 

The naturally aspirated Porsche engines since Variocam was introduced are not anywhere close to linear or flat in their torque development.



What is happening between 2000 and 4000 rpm is anything else but linear. Of course it might give you a rush as you exit the variocam zone and the engine is finally allowed to do it's job wrt power and not wrt all the secondary objectives.

Now, what you have with those engines is a rpm band where you have effectively exponential power development. That's gotta be fun when you are in a position to tolerate the high rpms required.

The 991.2 engine is not only missing any range where it is exponential (or quadratic), it even stops being linear above 5000 rpm, and has a lower redline to boot. At that point you are in the classic zone where the 991.2 car just gets faster but not more fun, whereas the 991.2 has a (higher) zone where it gets louder but not much faster.

 

well - that escalated quickly....

 

I went 991.1 and don't see that on your graph unless you were agreeing with me?

 

I don't perceive that as valvetrain tapping. It seems to come from a source outside the engine (but probably still inside the engine compartment).

If you have a friend with some audio equipment I would use a directional microphone and a headphone amp to narrow down where it is coming from. You can't really do without because the sound is reflected inside the engine.

As a starting point, dampen the floor. Put some non-reflective material (carpet or so) under the engine. That allows you to figure whether what you hear is mainly reflected off the asphalt (and hence is originally projected downwards) or not. You can also shift around a small piece to further figure what the original direction of the sound is (judgement should be done by a stationary person, not the one moving the carpet).

 

I would have chalked your post off as sarcasm, except I remember reading this rumor (of the 911 going back to aircooled) elsewhere. If you have more information on this, then it might warrant creating a separate thread.

 

Not enough coffee on my part. I don't really disagree. I was just making the point that linear is not a good way to describe the development over rpm. Whether the observer likes it or not.

No offense meant.

 

not offended at all!

Here's the thing.... I smoke a lot of cigars and have for years with >10,000 in my humidor. Still, there are cigar nerds that try to describe every nuance on their palette for each cigar. I just generally talk about If I like it in general.

the 3.8 is kind of like that. Linear, unlinear? Torquey, not torquey? It all depends on what you are comparing it to and all I know is I like it and it just does it for me. These discussions online can be fun but the data doesn't matter to me or some of the 3.4 guys. That's because you can't quantify emotion and this is why anyone presenting data as fact, doesn't get it. Those that don't get it may experience the same emotion with their smaller, compensating ( that jab is meant as humor) engines. We can however agree that there is nothing like a Porsche 911! And we can agree the engines in the 991.1 is bigger so... mines bigger than yours. That's why you have to compensate!

 

That could be the sound of high pressure injectors at work. It has been there since the 991 was introduced, but is more obvious with the higher pressures of the 991.2.

 

Lol. It was definitely sarcasm, although I have mentioned it on this forum before as a joke because that is what I was told by a mechanic. With emission requirements, I do not think it is possible to go back to air cooled.