Sorry I have been away. Working kinda hard.Very interesting modifications:
1.May I ask you why you chose billet conrods? Billet conrods are inheritendly weaker than forged con-rods, so my question is why didn't you choose some custom made forged conrods from carillo or similar.
2. Can you give a number for the weight savings using your pistons and con-rods?
3. Oil consumption: Once finished I would love to get some information on the actual oil consumption of your engine.
On the billet rods, the 4340 rods are forged prior to machining. The entire billet is forged. The process of forging prior to machining has been an aerospace practice for years because forging after machining causes differential stresses in the material which frequently causes shape changes. The most important consideration in machining after forging is controlling the temperature of the material during machining to prevent overheating the material and reversing the quench and softening the material. It also preserves the grain flow in the crystalline structure of the billet and results in the strongest rod for the weight.
On the manufacturer, it was convenience. I am familiar with 4340 chromoly and 2618 aluminum used in the pistons. Plus, it was Mike Levitas' recommendation and has been used in other rebuilds, and who am I to second guess his vast experience. I've done some first order calculations and the stress in the rods will support RPMs well above 11,000 with strength margin. As I said, I am more than doubling the loads, so I was particularly interested in increasing the stiffness in the rods to minimize cyclic harmonic loads. The H beam is stiffer than the stock I beam. I may be overthinking the problem, but if the rod natural frequency is a low multiple of the RPM, you are loading the crank and wrist pins significantly more than straight inertial load calculations would indicate. I'm sure Carillo rods would be just as good as Carillo has a great reputation.
On the weight, I do not yet have the data on the stock pistons. You can feel the difference holding them, so I would say the weight difference is in the neighborhood on 10%.
On oil usage, the Nickel-silicon carbide coating will take longer to seat the pistons than the stock Lokasil, so I will be tracking oil consumption closely. Because of the slower ring seating, I would expect the engine power to increase slightly above the initial tuning runs.