Question about ring sizes ...

[jatchis]

I see a lot of ring sets for the Ford 2300 sold in either .035 oversize, or what they refer to as .030 +5, yet pistons are not sold in a 3.815". What is the reason for the additional .005" diameter on these ring packs?

Sorry, may be a stupid question, but I've always wondered about it ....

[PitManArm]

No such thing as a stupid question. Rings come in +5 oversize so that they can be filed to get the correct gap. Usually it isn't a concern it the cylinder walls are freshly bored and honed, but on a rering of an older combination it is sometimes difficult to get the gap close.
If you don't need them to get the gap correct, then the added tension will likely work against you.
Not just the 2300, but most popular engines have these rings available.

[boportt]

who r u kiddin thers an assload of stupid qestions on here. but that's rite bout file fit +005" rings

[jatchis]

Yeah, I've read the term "file fit" used in association with the +.005 sizes, but I always thought that all rings were "file fit" in order to achieve proper end gap, or is this something else entirely?

I have also run into the fact that I can't find anyone online that lists a set of Total Seal gapless rings in .030", I can only find them in .035". Does no one run the gapless rings in a fresh cut .030" over block? Or do they just use those in blocks with wear on the overbore?

I'm confused ....

[boportt]

ya u r confsed cuz wen u build a race motor u use file fit rings so u got perfect end gap. stock replacement rings aint perfect enuf but u aint fast any way so just get some stock oversize rings

[jatchis]

Aight, bo ... 'preciate the info. Rings ordered. ;-)