Connecting Rod Tech

[FordNut]

Doing a little research on rods in planning process for a buildup. All the discussions and explanations I have seen are purely based on strength and nothing I have found addresses performance issues. Most billet rods are I-beam while the forged rods are H-beam. I wanted to find out about performance rather than durability. Specifically, which design has more rotational resistance due to catching and holding oil that is slinging around (H-beam ?) and which has more resistance due to the large flat surface slapping against the oil that is slinging around (I-beam ?). I found no such comparisons but assumed there is indeed some performance gain to be had with rod selection. The only performance comparisons I found were based on lighter weight.

Then I found a couple of specialty manufacturers of billet cross-beam rods. They are similar to I-beams except they only have one cross beam in the middle of the rod instead of one on each end. This provides for a more thin, streamlined surface to impact the oil that is slinging around and potentially free up some power from parasitic losses, they also feature lighter weight, and still have high strength. Some NASCAR teams are using this type of rod.

Just thought I'd share the info, they're expensive so I'm not convinced I have to have them but apparently it's the latest thing.

[DEFYANT]

Would a "windage tray" help with the airated oil concern?

Thanks for your reasearch.

[JohnE]

The mass of the rotating assembly becomes more important as the rpms rise. It takes a lot of force to change the direction of the mass involved. The oil idea is small in comparison.

The factory powdered metal rods are actually a good compromise. Just do not ever spin them faster than 6250rpm. They will take a lot of force in compression, but become disconnected rods when asked to pull the pistons down at high rpms.



I am running Mainley H-Beam rods and Diamond pistons with a ballanced cast crank. There is a loss in fuel economy over my stock engine. Durability is the reason I built it. So far I've gotten 80,000 miles with a 9psi supercharger. It even survived a tank of bad gas pulling my boat.



John

[FordNut]

Would a "windage tray" help with the airated oil concern?

Thanks for your reasearch.
I believe there is already a windage tray, but what I'm referring to is oil as it drops down to the pan.

There is also another rod design I saw reference to but found no data, that is the A-beam rod.