truckdoug

iTrader: (25)

so I'm trying to get all my ducks in a row to fix my hurt motor (went lean on the rev limiter at ~15psi)

i am seeing there are two different stock ring sizes for 6.0's

gen 3's got a 1.5 - 1.5 - 3.0 (mm)

and true gen 4's got a 1.2 - 1.5 - 2.5 ???


without a piston in my hand to measure, can I say for sure which ring pack I need?

also I'd like to try a napier type second ring. are these available in 4.000 bore?

LLLosingit

iTrader: (4)

Do you already have the motor apart and know for a fact that you didn't hurt the cylinders? If not you might want to start there before buying parts.

JHZ28

iTrader: (3)

It looks like 99-06 are the same size rings at 1.5 1.5 3.0mm 04 up should be gen 4 floating rods

KCS

iTrader: (20)

I agree with this. Make sure the cylinders don't need to be honed or bored out to repair before buying rings.

If not, I would suggest either Mahle 41858CP if you have the 1.5/1.5/3.0 rings or 42084CP if you have the 1.2/1.5/2.5 rings. You should be able to find them for ~$50 and they have a Napier second ring.

truckdoug

iTrader: (25)

thanks guys i'll take a peek at the turkey today

pantera_efi

iTrader: (1)

Hi, I fit NPR Brand rings when possible.
I use the Steel top, the "N" second, and the standard oil tension.

Lance

64post

iTrader: (5)

Is that "N" 2nd a Napier or beveled faced for help with oil control? NPR isn't that a Japanese OEM piston manufacture? Nippon?

truckdoug

iTrader: (25)

yes NPR is nippon piston ring co

looking though their pdf catalog is confusing as all hell

no idea what rings the 4" 1.5 1.5 3.0 set they list has in it or who carries them.

probably go with the mahle/PC KCS suggested

64post

iTrader: (5)

Where do you find any good ring set with Napier 2nd for $50 a set? Those are $111 from Summit and much higher from other suppliers. I'm looking for a set right now for 4.030"

KCS

iTrader: (20)

I got the 41858CP for a 4" bore for ~$50 from summit. I won't be using them, so they're looking for a good home if anyone else needs them.

I didn't look at the smaller rings though, but they're still less than $100 from summit as well.

JHZ28

iTrader: (3)

50$ shipped for the rings?

truckdoug

iTrader: (25)

yup ringland busted. haha i didnt even notice it being down on power, just thats it was puffin out the breather.




cant find the NPR's lance mentioned anywhere, so mahle/PC it is!

Thanks for the part number KCS!

64post

iTrader: (5)

I couldn't find NPR''s for 6.0 catalogued either, I know their parts are good quality for imports.

KCS

iTrader: (20)

Is that an offer?

No problem, happy to help. How does the cylinder walls look?

truckdoug

iTrader: (25)

I found a set of NPR's for the GM 4.000" bore 1.5-1.5-3.0mm ring pack but they are traditional style 2nd ring and a moly faced top ring.

they have a napier 2nd ring set for the 1.2 1.2 2.5 ring pack and another non stock application listed with the 1.5 1.5 3.0 pack for a 4.000" bore but it has a smaller ring ID than stock...which I assume is for a custom piston.

KCS, the bore appears fine, my plan was to run a ball hone through it and slap another piston in it.

but it looks like plans have changed a little