Piston steered & crank steered

I've been looking through some piston & rod options. Probably going with some gm style pistons because it would be cheaper to get forged one's to save weight.

I'm just curious because from my knowledge, most other manufacturers use crank steered. But most of the H-beam rods don't have the width to necessitate crank steer... or do they?

I've been reading and some people don't even consider the lack of centering an issue, but my gut leads me to providing a steering method.

The issue I'm finding is that I'm not sure whether the piston will have the correct width to be piston steered, but I'm guessing most H-beams don't have the width to be crank steered.

Asking the T-brick Titans for advice & wisdom

After searching some more, some have claimed that johns rods are crank steered. Is this the case?

If you're set on using the chevy pistons, and I'm not sure why.... Order a set, or find a used one. I'm not sure if cheap chevy forged pistons will be lighter. Good forged volvo pistons are ~ 400g each.

If the distance between the pin bosses is smaller than the rod small-end width, you can open the pistons up for the proper clearance.
If the distance is bigger than the rod width, you can have spacers made to fill the gap.

JVLs rods are crank steered, and 160mm center to center.

JVL is said to have his kit of H-Beams and forged Pistons dialed in. Others do as well. The development is already done. Spend the money for something that works and FINISH the project rather then talking about it.

I have nothing to add to the question, but wanted to say when I built my B230FT I bought stock Mahle pistons. Rings came installed and I didn't have to adjust the gap (checked it obviously), when I put them on the scale with the wrist pin sitting inside of the piston, they all weighed exactly the same, down to 0.0000, that was the limit of my scale, not sure Chevy parts would have that close of a tolerance.

Can someone explain in plain words (or pics - videos) the difference between Piston steered & crank steered ?? I think many people would like to see this ..

aristg said:

Can someone explain in plain words (or pics - videos) the difference between Piston steered & crank steered ?? I think many people would like to see this ..

Click to expand...

The "steering" of the rods describes how the rod is located axially. Without either end steered, the rod can float front to back on the crankshaft and wrist pin. The b23 had crank steered rods, with ~5-10 thou of clearance between the crankshaft and big end of the rod. Late b230s on the other hand had floating rods, with around 4mm (160 thou) of clearance.

Crank steered rods are guided front to back by the big end of the rod, on the crankshaft. This means if you installed a rod on the crank out of the engine, it wouldn't have any (significant) play along the journal, and would only be able to spin. Conversely, the small end of the rod installed in the piston is free to wiggle around a bit. The GM rods/pistons in my LS engine have around 1/4" of play. You need play at one end or the other, or else things will bind up.