5.9 magnum Piston Options

[Woods74]

Hi there, I'm having a hell of a time finding what I need. Stock Replacement pistons are Sealed power H655CP. I know this. Information doesn't Abount about options on this subject.

How about this:

If I order a set of say 405P, or KB362 pistons, can I use the rings from the H655CP? Or are they special (due to metric size)?


What works?

 

[omahamoparguy]

I dont think it would be wise to use the magnum rings in the "standard" 360 type of piston. The magnum uses 1.5 mm first and second rings and a 4 mm oil ring. the old type of pistons like the KB 362 use 5/64th's first and second and 3/16th on the oil ring.
dont know how this compares but i'll bet the Mag's are thinner.
Also one thing you should consider is that the magnum's used a slightly different rod,(that is thinner at the top) the magnum pistons had a piston that corresponded with this rod. you could use the old type of piston on the magnum rod but there would be more side to side clearance between thetop of the rod to the pin boss on the piston. It might not matter much in a daily driver but using the matching rod/piston combo would make for a stronger design. By the way the magnum rods are lighter too due to their narrow top section.(the part that the pin rides in). this makes the balance different too.

 

[Woods74]

Just Wanted repeat for good measure: There is no intermixing of stock 5.9 Magnum pistons/rings and after market ones. Saying "Ah, just throw it in there!" doesn't work. If your rebuilding with a kit, add pistons as a set of 8, and add rings and possibly rods to the equation.. Then get it balanced.

Thanks so Much!