Reposted in Tech/Misc.

I've been running an '89 h22 swap for about 3 years now and it's time for some new piston rings. I'm having trouble finding some good info on the difference between standard and low pressure rings.

I've read about tangential pressure and cylinder wall pressure and how standard tension rings exert pressure around 180-240 psi, while low tension rings are around 90-160 psi. It's clear to me which deliver the least amount of friction and that sounds good to me and my cylinder walls. However, I'm running a 11.0:1 cr and I'm really not sure if the low tension rings would do the trick. I'm assuming a compression test would yield numbers higher than 160 psi (even though I haven't done one yet and I'm not going to till new rings are in place. I don't even want to know how bad it is right now).

Is the math that simple? If an 11.0:1 cr yields over 160 psi on compression testing, would a low tension ring rated at 160 psi max be insufficient? That would make sense to me, but I'm not pretending to know something I've never dealt with before.

After further reading it seems the ring I need will be more decided on whether or not I have shallow or deep groove pistons, and I don't know the answer to that one either. Anyone care to enlighten me?


Modified by liquid51 at 5:18 PM 10/9/2007