Why so rough?
Safety Car
Joined: Feb 2013
Posts: 4,875
Likes: 1,174
There have been reviews where this has been noted as actually designed into the engine. That is, purposeful. Some reviews called it a "feature".
I think it is part of the experience... a big, V8 with lots of power not wanting to sit still and rumbling away. That is what the reviews inferred anyway. Who knows if it is true but I like it myself.
I think it is part of the experience... a big, V8 with lots of power not wanting to sit still and rumbling away. That is what the reviews inferred anyway. Who knows if it is true but I like it myself.
Safety Car
Joined: Dec 2007
Posts: 4,070
Likes: 160
From: Coralville Iowa
It very likely IS related to the cam profile. Another contributing factor is likely the overall stiffness of the chassis and the motor mounts. If you watch the tachometer carefully at idle it really doesn't vary that much but the "feel" is exaggerated.
Burning Brakes
Joined: Mar 2013
Posts: 1,135
Likes: 14
The tach displayed on the screen is electronically "damped" to show a steady easy to read needle that doesn't constantly shake like old mechanical tachs...wouldn't show evidence of a rough idle.
Drifting
Joined: Jan 2003
Posts: 1,327
Likes: 17
From: Maryland
Definitely a feature. If you want a smooth idle, go buy a Cadillac, BMW, Benz or Lexus. I say that with the utmost respect. Pull up in a Corvette, Porsche, Viper, Camaro, or Mustang and the "Feel" is part of the experience. Hell I said BMW, Caddy, and Benz when I know damn straight that they too have their Vs, Ms, and AMGs that feel like that 5.8 Earthquake LA had last night.
Instructor
Joined: Oct 2013
Posts: 136
Likes: 13
From: Tennessee
My C7 Z51 idles rough too. It's smooth as silk on the road under load. No vibration at any rpm. But the idle is rough. I wonder if this could be causing it?
http://forums.corvetteforum.com/c7-t...cs-inside.html
I'm going to take a look when I have time..
http://forums.corvetteforum.com/c7-t...cs-inside.html
I'm going to take a look when I have time..
Safety Car
Joined: Feb 2013
Posts: 4,875
Likes: 1,174
My C7 Z51 idles rough too. It's smooth as silk on the road under load. No vibration at any rpm. But the idle is rough. I wonder if this could be causing it? http://forums.corvetteforum.com/c7-t...cs-inside.html I'm going to take a look when I have time..
Le Mans Master
Joined: Apr 2005
Posts: 7,361
Likes: 4,800
From: West Burbs of Chicago IL
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Team Owner
Joined: Sep 1999
Posts: 41,732
Likes: 1,718
From: Springfield MO
There have been reviews where this has been noted as actually designed into the engine. That is, purposeful. Some reviews called it a "feature".
I think it is part of the experience... a big, V8 with lots of power not wanting to sit still and rumbling away. That is what the reviews inferred anyway. Who knows if it is true but I like it myself.
I think it is part of the experience... a big, V8 with lots of power not wanting to sit still and rumbling away. That is what the reviews inferred anyway. Who knows if it is true but I like it myself.
Drifting
Joined: Jul 2009
Posts: 1,358
Likes: 59
I would like to hear from a gm engineer on this issue. I was wondering if it is a combination of the direct injection/higher compression(think diesel here) and the cam driven fuel pump putting a significant load on the engine at idle rpms. The cam is not aggressive at all, as far as affecting the idle. I personally do not like the idle sounds...maybe I need a louder exhaust.
Racer
Joined: Mar 2014
Posts: 321
Likes: 84
From: Marco Island FL
