Alternative to wossner piston rings?

[nicdav]

Hi there, i'm after an alternative rev of rings for my Fiat coupe 16vt? Piston size is 86.4mm , 0.4mm over size! I will be grateful of any help as engine will be stripped down within next few days. Nick

[Guy Croft]

I regret that I do not know of a source for them except perhaps Fiat themselves - although your pistons may be formed for thinner 'race' rings.

What exactly is the problem - as you understand it with the ones from Wossner? And were the old rings actaully made by them? I might be able to remark in a helpful way on that.

It is completely unheard of (in my experience) for a ring pack - per se - to give any problems.

GC

[Boyracer]

Slightly related question...

I have set of used Wössner forged pistons (6000 miles or road use) that I intend to use in my BMW project. Set of used but intact rings came with the pistons and I wonder if I could reuse them? Sorry if this stupid question but I haven't found anything definite on this subject from books or internet, maybe this is clear to all professionals but I'm complete beginner on engine building.

[Guy Croft]

You can actually do and I have done it (on a Lancia 037 engine many years ago when I had to resort it because I couldn't get rings from Mondial for the forged pistons) but only if if the rings are in low-hours run condition, not worn sharp-edged and the chrome or moly coating/facing is still intact, but check the end gaps first, there is plenty written in the GC V/W (Virtual Workshop) on this. In order to make the bores ready you should FlexHone the bores and detergent wash thoroughly, read the att. Treat the engine as 'new' and give it 400 miles bedding-in on non-synthetic oil like Castrol 10W/40.

G