You may already know that GM’s current range of Gen. IV small-block V8 engines is the most popular line of eight-cylinder engines on the planet; but stricter emissions and fuel economy requirements may have a negative effect on the success of the powerplant line. That’ why General Motors’ goal is to redesign the combustion system of the next-generation small blocks — called Gen. 5 — with direct injection to allow for a more efficient burn.
Allow John Rydzewski, assistant chief engineer for small block engines, to tell you all about it:
Comments
Wonder if pushrods are going away as well??
Yes pushrods are going to be replaced by a valve actuation tube.
How about an overhead cam perhaps?
are you joking or just talking out your rear? a pushrod IS a valve actuation tube. what do you mean? some new fangled pneumatic/hydraulic actuation system?
what you said makes no sense.
There’s no need for overhead cams they will stay with a cam in block V8. This gives an engine the smallest external dimensions and lightest weight per horsepower. And a lower production cost.
And a lower center of gravity.
Overhead cams are so 1995…
Yes pushrods are going to be replaced by a valve actuation tube. Explain this engine type please. Either Main wayne or Alex Luft
A cam inside of a cam,similar to what is in the Viper,is coming.
sounds like standard Variable valve timing tech to me.
GM V8s are already far ahead of Ford’s on mpg, that a new unit has to have them quaking in their Ecoboots! (intentional typo)
Push rods are here to stay at the moment. Variable valve timing with the single cam in the block will evolve into true variable valve timing. Like the L99 in the automatic transmission-ed SS Camaro and L9H in the trucks,the phaser advances and retards the whole camshaft, LSA,( Lobe Separation Angle ) is fixed with the grind,limiting adjust-ability. The cam in cam design,like the viper uses,allows for more adjustment,further reducing emissions and flatting the torque curve. I heard from an inside source that it was on the drawing board,but I’m not sure when it will appear. Now, four valves per cylinder,how are they going to do that with a single cam in the block engine? It will take some thinking out of the box.
http://www.mechadyne-int.com/vva-media/display-media/TVP-and-camshaft.swf/400/326/sCP-cam-assembled-to-a-twin-vane-phaser-animation
Here is how that cam in cam works