Flathead piston ring question

Hi All,

Im building a basically stock 239 99A Flathead at the moment, and have run into something I cant find an answer to, maybe someone on here can help..

Im using an old set of .045 over Ford manufactured alloy pistons, four ring style.

obviously finding rings to suit these wasnt easy, but eventually I came across a set, which are Ford stamped too. Now the top and second rings are the same width top to bottom (0.93) but the depth they extend back into the piston land is different, there are two sets of eight, one are 0.142 and the thinner ones are .113 .

The piston Lands in the pistons are dimensionally identical, So dont help me decide which set goes where? Im leaning towards the deeper rings at top,more pressure on the bore, and the thinking being less room behind them for carbon to build up? the second ring acting more as oil control. Is this sensible ?

any engine builders care to comment?

 

What markings are on the side of the rings and are there any bevels on the inside of the ring id.?

Tig.

 

no bevels at all, the rings have 'Ford' in script and 'TOP' on them.its sort of etched in.

 

This large envelope had a Ford NOS 4 ring set in it.
Maybe this will help. I had to scan half of the envelope at a time.

 

The top ring is usually plain, the second ring has a dot on the top.

 

The second ring has smaller radial wall as it requires an expander behind it.Top ring thicker radial all requires no expander. Perhaps your expanders are missing?

Tig.