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Cp pistons I’ve got for 1JZ-GTE street/daily, come with low tension oil rings, will that have some impact on oil consumption and/or emissions?
The oil consumption will be higher than with high tension oil rings but the power will be more too with low tension rings.
That means, for emissions controlled street engine I’ll have to get standard tension oil rings?
I think that emissions are easily controlled with a standalone ECU. You can lean the mixture while you are on a emissions control test, then fire it up.
Normally low tension oil control rings are used with a dry sump system where crank case pressure can be a vacuum. That's not to say they can't be used in a wet sump engine but you may end up with more oil consumption. Here's a good read on the subject of ring tension from Wiseco: http://blog.wiseco.com/standard-ring-tension-is-a-myth