Cast Iron Rings vs Others?

vesnyder · vesnyder's Garage

I am rebuilding my 914 Type 4 motor and just bought some cast iron (Hastings) rings. The machine shop I am using told me "I would not use these on my lawn mower"? He said the others are chrome or moly (from manufacturers like Speed Pro) - but when I priced them it was $50 vs $150. I've been told from other T-IV engine builders these work good. What do you guys think?

BTW - My original rings, which looked like chrome, did not seal and that is why I am replacing

Eagledriver · 07-10-2008, 10:40 AM

I'm no expert on ring types but I suspect that cast iron rings will wear out sooner. That might not be a bad thing in your case since the last set didn't seat, maybe the softer rings will be more likely to seat. I'm sure that even if they do wear out sooner it will be many years before you have to replace them. They are more likely to not wear out your cylinders as well.

-Andy

MatthewBrum · 07-11-2008, 10:02 AM

I'm also no expert on rings but I think cast iron is the way to go.

Steve@Rennsport · 07-11-2008, 12:51 PM

Cast iron rings have some attributes: they are cheap and they seat quickly. For some, thats reason enough to use them.

Beyond that, there are better choices depending on many variables and expectations about engine life,..

vesnyder · vesnyder's Garage

Thanks for the input. Cast iron it is!

JFairman · 07-11-2008, 02:49 PM

When you buy JE pistons they specify and recommend Hasting cast iron moly rings.

Steve@Rennsport · 09:56 PM

Quote:

Originally Posted by JFairman

When you buy JE pistons they specify and recommend Hasting cast iron moly rings.

Buying & using as many JE's as we do, I think its more accurate to say that ring choices have more to do with cylinder material and application, rather than a blanket recommendation,....

We use a LOT of Goetze (OEM Porsche) rings as well as special plasma-coated ductile iron ones for turbo applications. We also use some Total Seal gapless rings in the second groove (special versions for Nikasil cylinders).

"Horses for Courses", as they say,...

m42racer · 07-11-2008, 08:06 PM

From what I have seen and been told, the saying goes, hard liner soft rings, soft liner hard rings, never the same.

So with Nikisil liners you have to use soft ring material. Here's where it gets tough. The Moly Rings as Steve stated are some of the best, but any detonation will kill them. Thats where a tool steel ring would work best, but the Nikisil kills that option. So making sure there is no detonation is the key. No chrome on our liners. The new thinking and some good results have come from the Ductile Iron nitided Rings.

I am also told, Porsche spec's out from Mahle the same Top and second ring in some kits. This works OK on mild NA engines but has very poor Oil control.

The use of these now special 2nd rings seems to be vogue and they have made a big difference. I am not sure what they are as this sort of thing is kept secret. These are the secrets that engine builder keep to themselves.

I had a V8 engine built recently where the ring package cost $ 1250.00. The rings were extremely thin, I think 1/32". When the Pistons were fitted they fell to the bottom. Short life, but the technology is quite amazing. Your best bet is to call some of the respected builders and ask their opinions. I think Steve's suggestion will be very typical.