Ring material pro's and con's, steel top ring vs cast ring?

[turbovanman²]

Was doing some surfing the other day and came up across quite a few threads on rings in boosted engines, top engine builders suggested using a steel top ring vs the OE's cast top ring, reason being, the moly can flake off with detonation, Hastings confirmed that is true.

So based on that, is it myth that the steel ring wears the bore more or just stick with the moly ring? I've found a set from Hastings with a steel top ring, its for an 81-82 L body.

[Spraynlog]

I think the moly rings work better on a rebuild/hone job like the ones I've done in my driveway, they can conform better to slightly out of spec bores. I think steel rings would wear the bores, since the bore is cast iron.
Of course, detonation will cause all kinds of havoc, including melted aluminum pistons. (don't ask me how I know!) I'm not a top engine builder, and I'm not sure what kind of power levels we are talking about either.

[GLHNSLHT2]

hmmm wonder what the top ring is on my hastings rings I just got

[turbovanman²]

Jay, the cast ring with moly coating is the M in the part number, so for us, I think its a 2M4206? If you want the steel ring, its a 2C5652.

Hastings told me their steel ring is lapped so no issues about ring seating.

[Ondonti]

Thats why they are suggested for mild turbo setups and thats it. I went chrome on my Daily and I don't know if they will seat thanks to my awesome cylinders.

I guess another problem some rings have is losing tension when boosted. Moly rings tend to be made from the material that does that.

[RoadWarrior222]

I heard you practically have to knurl the cylinders rather than just hone them to get chrome to seat. Would imagine plain steel or cast iron needs a rougher hone too.

[turbovanman²]

I heard you practically have to knurl the cylinders rather than just hone them to get chrome to seat. Would imagine plain steel or cast iron needs a rougher hone too.

Did you miss what I wrote earlier?

[RoadWarrior222]

What if I thought you were wrong

However, I am now understanding that Hastings calls for a 280 grit finish for any of their rings... which is considered rather harsh for moly, so no wonder they think their moly rings flake easily....

[Ondonti]

I went with a 220 because of the chrome 280 is on the rough side from what i have seen for moly.

No idea what they mean by lapping rings. On a moly ring the best hone would be a rough cut then a plateau hone that cuts down the peaks, instead of just doing a really light hone. That way you have deep groove for oil travel but flat surfaces that won't tear up the moly surface.

[turbovanman²]

What if I thought you were wrong

However, I am now understanding that Hastings calls for a 280 grit finish for any of their rings... which is considered rather harsh for moly, so no wonder they think their moly rings flake easily....

ALL makes of rings can flake, not just them. At least they were honest about it.

---------- Post added at 08:57 PM ---------- Previous post was at 08:56 PM ----------

I went with a 220 because of the chrome 280 is on the rough side from what i have seen for moly.

No idea what they mean by lapping rings. On a moly ring the best hone would be a rough cut then a plateau hone that cuts down the peaks, instead of just doing a really light hone. That way you have deep groove for oil travel but flat surfaces that won't tear up the moly surface.

They lap it in, like a valve. Phone and ask, they are really friendly.

[zin]

The "softer" cast rings will wear faster than the steel or chrome, but that means it's ring material that wears away and not your bore...

If you really plan on abusing things, Hell Fire rings are a pretty good choice... Ductile Iron, tough stuff, but easier on the bore than tool steel...

I have to say that I have yet to find a ring material/maker that wins hands down, there always seems to be some chink in the armor of whatever ring you choose! Either it wears out "too soon" or wears the bore, etc, etc.

Personally I think it matters more that the bores are properly prepared, that is, bored with a plate, and final honed with the proper stones for the rings, whatever they happen to be. Also a good idea, but not offered by many machine shops, is to lap the bores with leather to clean out the microscopic pores of the bore of all the bits of stone, etc so they don't find their way into the ring lands... But then again, I'm a bit "particular"...

Mike