NPR Piston Ring gap

[GavinT]

Test fitting shows a gap of .010” on #1 ring across all 4 cylinders. The NPR fitting instructions say not to adjust the gap as the rings are manufactured to meet Lotus specs and are 910 engine specific. Does running right on the edge of clearance specification bother anybody?. Engine is an 88MY 910 Turbo with Bosch CIS, USA Spec.

Thanks!

[drdoom]

https://www.speed-talk.com/forum/viewforum.php?f=1

The link attached takes you to Speed Talk Engine Tech, hosted in the U.S. Contributors range from average Joes to comprehensively qualified specialists. NPR rings were a recent topic, apparently given top marks by those who know. Recent reading on ring gaps seemed to downplay concerns for loose specs, just emphatic on not going too tight. Search function works quite well, BTW.

Cheers

[GavinT]

Thanks for the link Steve.

The issue I’m concerned about is that .010” is right at the top of the spec range and NPR say not to re-gap the rings. So I’m looking for some validation that it is ok to install with a .010” gap.