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VVT on L84/L87

BenThere

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BenThere Enthusiast

BenThere

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I've been on the internet looking for a description and diagrams of how Variable Valve Timing works on m new 2019 Silverado.  I can find all kinds of stuff I already know in general about VVT, but nothing on the specifics of Chevrolet's/GMC's specific system.  What's going on in there, what does it look like, what's under those "domes" on the valve covers, etc.  Anybody got any links to the Chevrolet/GMC specifics?  

BenThere Enthusiast

BenThere

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11 hours ago, CamGTP said:

This article by Hotrod should give you the best break down.


The design has stayed pretty much the exact same since they started using it back in 2007. You can't change much when these engines are still using 1 camshaft and similar style valve train.

 

https://www.hotrod.com/articles/hrdp-1007-gms-variable-valve-timing-system-performance-test/

That's a good article, thanks!  I found a similar article here, a little more current but same basic stuff.  Has some of the cut-away diagrams I'm looking for.

 

 http://www.superchevy.com/how-to/engines-drivetrain/1808-advantages-of-vvt-cam-in-gen-iv-v-engine/  

 

Still wondering what's going on under those "domes" cast into the valve-covers; my other, older LS engines don't/didn't have them.  

 

 

CamGTP Senior Enthusiast

CamGTP

Posted
Posted

The cylinder head and valve train design is different than the previous non direct injected engines. Nothing exciting, it's just the way they wanted to have the valve covers. it spaces the coil packs further away from heat as well.

 

COMPLETE-DRIVER-LEFT-CYLINDER-HEAD-2014-

 

 

BenThere Enthusiast

BenThere

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Posted
18 hours ago, CamGTP said:

The cylinder head and valve train design is different than the previous non direct injected engines. Nothing exciting, it's just the way they wanted to have the valve covers. it spaces the coil packs further away from heat as well.

 

COMPLETE-DRIVER-LEFT-CYLINDER-HEAD-2014-

 

 

Thanks for the pic.  So, there's nothing inside (under) those "domes"?  

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