More from gminsidenews:
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The engine photo was of the current LS9 block, the Gen V block will have the camshaft positioned higher in the block, a raised cam. A higher position cam in the block alllows greater flexibility in pushrod positioning and because the pushrods are shorter the are stiffer. Think R07 NASCAR as the inspiration. The Cam in the Gen V block will most likeky be even higher in the block than the R07, NASCAR has specific rules as to the height of the cam above the center line of the crankshaft, that do not apply to production engines. Due to DI being planned for the engine the cumbustion chambers will have to be changed from the current design. Again loock at the R07 heads cumbustion chambers and ports and you can see there is plenty of room for the (direct) injector to be on the intake side of the head centers between the two valves and very close to the center of the combustion chamber and that the rocker arms are well clear of the injector also. The earlier Wards Auto article talked about the heads having revised ports to provide clearence for the SIDI injector.
VVT is currently used on the LS series motors and will be used on the Gen V version of the motor. Currently the VVT system does not provide for independent variable timing om both the intake and the exhaust valves. However going to concentric, cam in cam, technology would all accomplish dual independent variable valve timing with no significant changes to the block. It is likely that both types of VVT will be used Gen V blocks, the current systems used on lower price point vehicles and the "cam in cam" system on preimum price point vehicles and in performance engines. The same may be true with head design, two valve heads at lower price points and three valve heads on preimum pricepoint and performance vehicles.
As to engine size a 5.2, a 5.5 and a 6.2. the 5.0 is a 3.87 bore and a 3.26 stroke (almost a return of the 307 that Chevy produced some 25 years ago) a 5.5 is the bore of the current LS9 and the 3.26 stroke of the 4.8 truck motor. The parts commonality with current motors reduces costs. Utilizing two blocks and two cranks gives three displacements to cover the entire displacement range. Add in two differnet head types, 2 and three valve designs, and two different VVT systems, AFM, SVIS (Stationary Vehicle Idle Stop) and you can get a very wide variety of engines that cover a large price point range from basic work truck to preimum vehicles like Cadillac sedans and the Corvette with advanced features that favor performance, economy, and emissions reduction.
This would provide a cost effective way to meet the needs for a powerplant family that has favroable packaging and is able to provide normally aspirated power levels of HP from 65 to 80+per litre competive withe DOHC designs.
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I left the spelling mistakes in :P
Rumour has it have the engine is also designed to accept DOHC heads on the same block.
What GM should have (with the pushrod motor at least) is a very under square engine with very short pushrods. Sounds like they are designed to rev! Not to mention the design is partially based on GM's nascar engine.
Dual Cam In Block is apparently unlikely but look at where the top cam is located on the DCIB pic above for an idea if the cam position. A "cam in cam" setup for VVT operations essentially makes a DCIB design redundant as GM only requires one block design for single cam VVT & "Cam in Cam" VVT.