Piston guided rods

[408 Nova]

Is there any power in running that setup over a "normal" setup?

[Walter R. Malik]

Is there any power in running that setup over a "normal" setup?

If the rod placement and side clearance have a chance to side load in any way, it can; especially if the crankshaft gets shorter dimensionally through distortion at higher RPM and big power.

[PackardV8]

While we're on this subject, how do you "guide" your rods?

1. One builder whom I respect spends many hours making individual aluminum spacers to insure each rod journal has three equal spaces.

2. One builder who claims no comebacks just stretches spirolocs and puts one on each side between the rod and the piston pin boss.

3. A third builder of smaller engines doesn't use any spacers or "guides" whatsoever. His claim, on a small cylinder bore and a 2" rod journal, there's not enough tilt to worry about.

[jed]

Read the foot notes. Then read those foot notes and it goes on and on.

[Jeff Lee]

The “slack” is made up in the piston construction although #1 is doable.

[Bill Chase]

While we're on this subject, how do you "guide" your rods?

1. One builder whom I respect spends many hours making individual aluminum spacers to insure each rod journal has three equal spaces.

2. One builder who claims no comebacks just stretches spirolocs and puts one on each side between the rod and the piston pin boss.

3. A third builder of smaller engines doesn't use any spacers or "guides" whatsoever. His claim, on a small cylinder bore and a 2" rod journal, there's not enough tilt to worry about.

Interesting video on YouTube. horsepower monster. Where they build up a ford Nasar engine for off-road truck racing. it gives a really good look at the piston pin, and the Mahle pistons setup for centering the rods. they too used more big end side clearance. not a technical expose' per se but does give some insight into how its accomplished with piston design. and it is a 4.125 or larger bore. https://youtu.be/1n3riPzd0W0