Davinci

During a recent top speed run I suspect I might have fried my rings, Im getting very high crank case pressure which results in abnormal amounts of oily steam from the ccv.

What rings would you reccomend to replace the old ones with? Im currently running about .9 bars of boost (13psi) on a stock engine. Are there any cheap oem pistons that are worth changing to while I´m in there? (Im not looking for a 700$ pistons, no matter how good they might be)

Xaendeau

Supertech pistons with Wisco rings. It's like $550 or so. Otherwise stick with the pistons you have, dingleberry hone the block with ATF for a couple passes, and slap new OEM rings on. Honestly, OEM pistons with aftermarket forged rods is a pretty common combo people do.

It it was my engine...new OEM rings, forged rods, kings XP bearings, nice aftermarket oil pump (are they available on the 1.6?), and a new timing belt.

However, you need to do a compression and leakdown test before you spend any money on parts. Gives you a better idea with what is going on.

x_25

If you can find a set, the automatic 1.6s had lower compression pistons. Good luck though, it took me four years of semi regular searching to find an actual auto 1.6 engine.

Xaendeau

I'm actually helping with a rebuild of an automatic 1.6 Miata with only 100k miles. One cylinder had lower compresson with a stuck ring found on teardown. They're redoing the valve stem seals, water pump, timing belt, front and rear mains, and head gasket while the engine is out.

They ordered a set of standard 1.6L OEM Mazda rings and find out the oil control rings are 4mm on assembly. The oil control ring gap on the pistons is only ~3 mm or so, which is odd since I though they all were 4mm on these engines.
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This car is stock as stock can be. It has only been repainted, so I don't think it had some junkyard pistons thrown in by a previous owner. However, the car is nearly 30 years old so...who knows.

​​​​​​​I tried searching the fourms, but couldn't find anything useful. Worst cast I'll see if I can get x4 oil control rings from someone like Hastings. Anyone every dealt with this before?

x_25

Last I looked, rock auto had some piston ring sets for the auto 1.6s with the 3mm rings. But yeah, they are a different size.

Xaendeau

Thanks for confirming. I'm less familiar with the 1.6L engine, so this was a surprise to me.