.01 Ring with Standard Piston

[Trnelson]

Unfortunately Fed-Ex let me down today, hopefully they will pull through tomorrow. I have been doing a lot of research and it does indeed look like a tedious process, lots of installing and pulling the rings back out to get it just right. Gotta be careful not to scratch up the bores during the process. 
I did receive the ring grinder and took a few practice strokes on an old ring, seems pretty smooth and material comes off pretty easily. I’m sure the learning curve will be steep but hopefully it flattens out after the first few rings. 

[madkaw]

I have also heard of his technique of using .010 over rings . I believe machinist told me that the one size over would still be concentric enough to do that .
It takes quite a large gap before it starts affecting CR . I thought there was two specs . One was the range for the gap and the other spec was replacement range - like .039 or something . I ran large gaps on my last L28 build . All the rings were at the far range , but I ran it . 

Id say - send it

[Trnelson]

Received the oversized rings today, as it turns out they are just a little bit longer. I spent several hours filing each one to each piston and I feel really good about it. I’m now well within tolerance and the overall shape seems fine. The only hiccup I had was not realizing that the lower compression ring is seemingly made of a softer material and I overground one 🤦‍♂️...  still a much closer fit than the standard size so I’m sure it will be fine. 
 

[Trnelson]

First picture is the standard size on top of the oversized, second pic is vise versa, third is the overlap in the bore prior to grinding and the fourth is halfway through installing the rings. Planning to install them in the block tomorrow, the only concern I have at this point is how the middle oil ring will fit. Thinking it will compress easily but it does seem quite a bit tighter that the one from the standard set. 
thanks for the input and advice. 

[Captain Obvious]

So it seems that I guessed right and the oversized rings came off the same fixture and were just left longer than the standard rings? Cool. That's a good piece of info right there. Might not be the case for all manufacturers, but at least the one you bought was made that way. So what brand did you buy?

And glad to see the math worked out on the overlap as they came out of the box. 

And as for the oil ring expander... I really have a hard time believing they were making different expander ring versions for STD and .010 oversized. That wavy ring is so compressible. I'm no expert, but I bet it's the exact same ring they put in the STD set. About the only thing they could do would be to remove two complete sections so the tips aligned. You couldn't remove just one section, you'd have to remove two. If you removed two sections that it would even wrap completely around?

[Trnelson]

Interestingly the standard sized set was Wiseco and the oversized came from TPR, a Japanese company.  I was concerned when I ordered but it looks like it will be fine.  Not sure why I didn't think to do it yesterday but I'm going to compare the oil rings from each set to see if there is any noticeable size difference.  I'm sure the larger, if it in fact is, would fit, however my concern would be if I  just smash it in there if it would hold enough oil being over compressed.  Probably overthinking things as usual.  

[madkaw]

I wouldn’t be concerned about the second ring being a little oversized . Conventional thinking has changed about the gap size on the second rings over the years . Now the engineers like to see a larger second ring gap to make sure pressure doesn’t build between the two rings and cause ring flutter . 
I didn’t have as good of luck with my oversized rings . The box oddly said STD- .010 . The gaps still came in too big .

Sounds like you have a winner !

[Trnelson]

I love it when I make a good mistake!!  Of course now I will have to take the other second rings back off the pistons and match them up... my OCD hurts sometimes.  I was impressed by the quality of the TPR rings, I'm no expert but the material just felt like higher quality than the Wiseco.   I'm not sure if you are planning something similar but if you are the process isn't too bad, a bit tedious and time consuming but once you do a few it goes pretty quick.  I have about 4 hours invested in the process, 1 of which was spent on the first ring.  Just be patient and "sneak" up on the gap your shooting for, I literally would take a measurement and need just one turn of the grinding wheel to get it where I wanted it.

[Trnelson]

Update: Engine is in and I’m about 100 miles into break-in. So far so good, it fired right up, sounds and feels good. Plan to put another 100 miles on it then change oil, coolant, filters etc. Plan to recheck compression then too just to see if the numbers have come up from pre refresh. 

[Captain Obvious]

Great! Last I heard, you were gapping rings. I didn't know you had the motor back together!

So far, so good, huh? Excellent! So did you do a compression test as soon as you put the rings in at zero miles? Just to see?

[Trnelson]

19 hours ago, Captain Obvious said:

Great! Last I heard, you were gapping rings. I didn't know you had the motor back together!

So far, so good, huh? Excellent! So did you do a compression test as soon as you put the rings in at zero miles? Just to see?

I have not checked compression yet, I wanted to let the rings seat for a couple hundred miles prior to testing. Probably be a couple weeks, damn job interferes with my play time in the spring!

here is a pic before I dropped it in

[siteunseen]

I too felt the same on compression testing when I rebuilt 2 motors. Never checked them to this day. Cars run great. Some things I don't need to know.