Filing +.005 rings to fit stock bore

bomber315

Member
So I'm in the process of freshing one of my motors (after 5 weekends) and building another new one.

I ran into snag. In my box of stuff, I have what apparently is a file to fit top ring. But all of the 2nd rings I have to choose from are showing .015 gap without touching them. I would like to see something more like .009.

Both of the bores measure nealy identical. (Down to the .0005)

I remember filing every ring to fit last year, including the bottom rings.

The question is... Can/ should I get +.005 low tension rings and file them to fit my standard bore?

Thanks
 
Only one way to get too .009 .
I remember the file fits being top ring only . Maybe thats changed .
 
Only one way to get too .009 .
I remember the file fits being top ring only . Maybe thats changed .
Well the top ring is the only one I see advertised as "file to fit" but I would like to have my 2nd ring tighter than .015 so I want to use .+.005 as "file to fit". Is that what everyone does?
 
I would say so . you can use .010 over as well .
The thing there is drag from spring tension .
Honestly i doubt there is a power increase in that .004 ring gap .
Are you lapping the ring land ?
 
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I understand not by akra or anything I'm just saying in general if it isn't in the rules. It won't hurt anything to not run one? Is it beneficial at all?
 
I would think the engine would smoke like a chimney. Maybe even to the point of running low on oil at the end of the race.
 
Wouldn't it work the same way as the 2 ring wiseco pistons? Some of those are only 2 rings and they don't smoke? Just curious as I have never heard of anyone not running the second ring on a 3 ring designed piston. Might be something I may have to try and see.
 
Most people running a three ring pston are bound by rule .
The newer wiseco 3 rings must be designed with durability in mind .
Trade off , of friction vs leak down .
 
Alot of two ring pistons use wider expander rings with much larger oil drain back holes . So my guess would be a 3 ring piston only using 2 rings would smoke really bad because of the oil being trapped and not draining back
 
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