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Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 4:48 pm
by Jeff V.
Rather than me reposting everything here, just go to the Corvette forum and read the first post.
https://www.corvetteforum.com/forums/c8 ... ncept.html
I'm wracking my brain trying to figure out what else that 2nd timing chain could be for, but I can't think of anything. Especially combined with that huge oil pump assembly. Has anyone got any other ideas, or could this really be an evolved XV8 style engine?
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 5:02 pm
by ChargerX3
Wonder if that ties into one of several things. Onboard electric start/helper motor, or if the VVT is chain based. Im not familiar with that motor, so its a bit hard to make out.
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 5:09 pm
by Jeff V.
Nobody outside of GM is familiar with that motor. That cutaway photo showed up for a fraction of a second inside an official GM teaser video that dropped on Monday.
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 5:31 pm
by Chris GTO TT
That's super weird looking
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 5:58 pm
by aaronatstate
I don't think its for a second cam for a few reasons. First, you can't see the second cam above the first cam, or even anyplace where the second cam bearings would sit. Second it looks like the second chain angles inward (like it is going to a smaller gear), where if it was going to a second cam, it'd be straight.
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 6:11 pm
by Jeff V.
:d ontknow:
I can't imagine what else it would be though. The chain angle could just be lens distortion in the camera.
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 6:22 pm
by aaronatstate
[quote=""Jeff V.""] :d ontknow:
I can't imagine what else it would be though. The chain angle could just be lens distortion in the camera.[/quote]
Yeah not sure what it could be. Agreed on the chain angle, but it still lacks a second cam, or even a spot for the cam/cam bearings. But I suppose it is possible the second cam is above the frame of the picture too...
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 6:25 pm
by Chris GTO TT
Looking back at it again it's gotta be something to do with the VVT setup.
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 6:43 pm
by ChargerX3
[quote=""Chris GTO TT""]Looking back at it again it's gotta be something to do with the VVT setup.[/quote]

Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 6:49 pm
by ChargerX3
Hmm now that i think of it. Maybe that second chain is there, so you can speed up or slow down the cam movement in relation to the rotation of the motor. Yea VVT adjusts timing on the fly, but this could potentially control duration as well. Speeding up or slowing down cam movement on the fly. That would be a trick setup allowing for even more dynamic control over timing/duration/airflow.
Re: Dual cam-in-block V8?
Posted: Tue Apr 30, 2019 11:06 pm
by mjannusch
I dunno, but it sure looks strange...
Re: Dual cam-in-block V8?
Posted: Wed May 01, 2019 11:36 am
by alienviking
It is for the flux capacitor.
Re: Dual cam-in-block V8?
Posted: Wed May 01, 2019 1:19 pm
by aaronatstate
I think it may be how they are doing variable valve timing with the pushrod V8 setup. But instead of using hydraulics to do it, they are using a mechanical link. Here is the company that made the cam for the Viper with VVT. Look at the cam bearings on the "DuoCam" and in the picture of the new engine. They look nearly identical...
http://www.mechadyne-int.com/products/duocam/
Re: Dual cam-in-block V8?
Posted: Wed May 01, 2019 2:06 pm
by vr4
[quote=""ChargerX3""]Hmm now that i think of it. Maybe that second chain is there, so you can speed up or slow down the cam movement in relation to the rotation of the motor. Yea VVT adjusts timing on the fly, but this could potentially control duration as well. Speeding up or slowing down cam movement on the fly. That would be a trick setup allowing for even more dynamic control over timing/duration/airflow.[/quote]
I'm pretty sure that's exactly what this is. Vvt to allow control over duration and overlap.