Like the title says, my paperwork from my machinist says the top compression ring end gap should be between .008”-.012”. and my 2nd ring end gap should be .016”-.022” and oil control ring should be .008”-.020”. My Haynes manual says the same thing for the b20z2. I’ve also found this same info from an online manual for the b20z2.

a little background on my build, NON VTEC, bored out to 84.5mm and have OE style pistons and rings. Stock cams, shaved head and decked block. Not anticipating driving this thing too hard. It’s in a CR-V.

All the info I’ve seen online suggest .008”-.012” is too tight for comfort. Seems a lot of people are running .016”- .018” from what I can find online. Granted they’re more intense builds. I’m non VTEC, never gonna see boost or spray.

I was thinking of playing it safe and running, .015”

For the 2nd ring I would probably run .020” but not really sure.

oil control ring, I was thinking .0.15”

would appreciate any input.

 

The engineers who designed the motor determined that the ring gaps listed in the service manual are the best option for that motor in a stock configuration. If you're making stock power with stock components then use stock ring gaps, its that simple.

If you plan on turbocharging the motor or something later then by all means make them wider.

 

That makes sense, I just haven’t come across any build threads on Honda tech running ring end gaps in the .008”-.012” range. The farthest I would build this engine is intake, Header, and maybe stage 1 Brian crower cams in the future, but I doubt that will ever happen.

Edit: not sure if stage 1 BC cams is still a thing. I can only really find stage 2 for sale. Even though I can find stage 1 BC in some catalogs online.