Cylinder Distortion

[Joe-JDC]

Hot honing is not effective unless you have the actual pistons that are going to be used and let them soak in the hot oil/water that is used for the honing.  They need to be measured at the actual temperature as the block to get the clearances desired.  Many shops do not think of this, and the clearance is not correct, so they say hot honing is not a good idea.  Joe-JDC

[Autoholic]

Joe, along those lines then wouldn't it be needed to soak the piston rings as well? While I agree that it's a lot of work to try and squeeze out a little more power, I would bet that the engine has better longevity and wear performance. I don't think every advancement or technique should be looked at for its power gains, the reliability gains could be a lot larger.

[cjshaker]

Joe is talking about the expansion of the pistons at temperature, which would determine the correct bore size at temperature. The rings would have no effect on that.

Doing this kind of work may be an advantage to F1, Nascar, Pro Stock, maybe Pro Mod and a couple of other big BIG dollar racing organizations, but it would hardly be worth it to anything less than multi-thousand/million dollar payouts.

[Autoholic]

I would disagree that expansion has nothing to do with the rings. While they probably have little effect on bore diameter, they will expand and impact the tolerances that the rings are installed at. Your gap could expand a little bit and when you're already hot honing the block, heating the pistons, you might as well heat the rings up as well. I'm not sure how likely you'll run into interference issues when fitting them, I know Ferrari dips their rings in liquid nitrogen to shrink them before fitting so that they fit. Something to think about.

[Joe-JDC]

Once the optimum bore size is established, then the rings can be file fit to work amazingly well.  Just one of those blueprinting things to double check.  Joe-JDC

[jimeast]

At first glance of your post, If Ferrari does this, I would think they are performing a cryogenic treatment on the rings, not a fitment cooling, unless the design differs to the point they can't be assembled like normal rings.

I know Ferrari dips their rings in liquid nitrogen to shrink them before fitting so that they fit. Something to think about.

[Autoholic]

The robots that perform this are called Romeo and Juliet. I looked back into it to make sure I was remembering this correctly. It is not the piston rings in fact, it is the valve seat. They designed the valve seat to need supercooling in order to fit.