Rings won’t fit in grooves on pistons.. HELP!



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Feb 26, 2020
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I’m partway through building the bottom end of my 383. I was just about to gap the piston rings but when I test fit them they won’t go in the grooves on the pistons…

Do I need special rings or something? 30 over TRW L2293 dome pistons and Hastings 30 over moly rings.

i most likely have the wrong rings there is different thicknesses look up your pistons and see what rings they use and compare with the rings you have
Probably need different rings, try checking with a machine shop, with any luck there will still be an old school machinist who can answer your question.
Seems like a simple problem...

Either replace the pistons or the rings.

As noted before measure the piston groves and buy rings accordingly.
Probably 1/16th rings vs the stock 5/64. About a .020 difference. Several sets of those on eBay list 1/16th rings.

You'll need new rings. But a simple feeler gauge check will confirm the thickness.
That piston uses 1/16, 1/16, 3/16, rings. Buy the appropriate rings and you’ll be set. What do yours measure?
You might throw a set of calipers on your ring lands before ordering just to make sure.
Do a couple of circuits around the ring lands with a piston ring land tool. Even though your pistons appear to be clean, you will be surprised at what comes out.
Al Bundy, a true Dodge Dart hero!

5/64 = 0.078125
1/16 = 0.0625

0.077125 - 0.0625 = 0.015625

Your trying to put a square peg in a round hole...

Another thing my dad always said...

" Measure twice cut once"