flathead pistons

[32fdcp]

when did Ford switch to domed pistons ?

[supereal]

I believe they were used in the 3 1/6" bore V8 from 32-42, with the flat top variety for the 3 3/16" from then on, so the switch was from the domed type, rather than to them.

[flatjack9]

Flattop pistons were definetly use in 3 1/16 engines. I believe 1936 was the last year for flattop pistons. Some of those years flattops and domed were mixed within the year. I don't believe I've ever seen a 3 3/16 flattop piston.

[rotorwrench]

The steel pistons were phased out for aluminum several years before the 239 for the 1939 Mercury 99A came on line. The tin can sleeves were still around on some but not all. Some folks liked those steel pistons. Ford played with a lot of different ideas over the V8 era.

[42merc]

On the V8 flathead, flat-top pistons were used from '32 to mid '35, 1936 thru 1953 used domed pistons.

[flatjack9]

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Originally Posted by rotorwrench

The steel pistons were phased out for aluminum several years before the 239 for the 1939 Mercury 99A came on line. The tin can sleeves were still around on some but not all. Some folks liked those steel pistons. Ford played with a lot of different ideas over the V8 era.

Not so. The steel pistons and sleeves were used on Ford and Mercury at least into 1940. In fact most engines is this era were steel sleeved.

[jimTN]

Dome pistons started during 36 production and continued thru 53. No doubt. early 36 engines had flat top pistons.

[rotorwrench]

Originally Posted by flatjack9

Not so. The steel pistons and sleeves were used on Ford and Mercury at least into 1940. In fact most engines is this era were steel sleeved.

By golly you are correct. I had thought it was prior to that but in was in that 39 40 range that they started using aluminum with all replacements being aluminum. There were both steel and aluminum pistons for the 99A. The 09A for the 40 Mercury were all aluminum. All were domed whether steel or aluminum on the 239 engines. I found some steel domed ones on flea-pay. The V8-60 used steel pistons through the end of production in 1940. The 9N engine had 99A pistons but it doesn't specify if they were steel or aluminum types.

[40 Deluxe]

Originally Posted by rotorwrench

By golly you are correct. I had thought it was prior to that but in was in that 39 40 range that they started using aluminum with all replacements being aluminum. There were both steel and aluminum pistons for the 99A. The 09A for the 40 Mercury were all aluminum. All were domed whether steel or aluminum on the 239 engines. I found some steel domed ones on flea-pay. The V8-60 used steel pistons through the end of production in 1940. The 9N engine had 99A pistons but it doesn't specify if they were steel or aluminum types.

I first saw 9N's apart in the mid-50's, and they were aluminum pistons. Not sure if they were original, though. Even back then, some had had a couple of overhauls already. The oil bath air cleaner intake was at wheel level and the tractor ran in a cloud of dust all day at or near full load. Other tractors were taller plus often had their intake stack a foot or more above the hood. Yet this little 119.5 cubic inch Ford kept up with tractors having 200 or 300 cubic inch engines.

[rotorwrench]

The 9N might have started out with steel pistons in 1939 but it was manufactured thru 1941 and the only difference between it and the 2N in 1942 was that they took the electrics away for the war years when they needed the materials for the war effort. The engine was basically the same till the 8N came out in 1948 and it wasn't much different. The 9N engine for the trucks was 1941 only so they were likely all aluminum pistons by then.

[flatjack9]

Originally Posted by rotorwrench

By golly you are correct. I had thought it was prior to that but in was in that 39 40 range that they started using aluminum with all replacements being aluminum. There were both steel and aluminum pistons for the 99A. The 09A for the 40 Mercury were all aluminum. All were domed whether steel or aluminum on the 239 engines. I found some steel domed ones on flea-pay. The V8-60 used steel pistons through the end of production in 1940. The 9N engine had 99A pistons but it doesn't specify if they were steel or aluminum types.

And all were domed in the 221 in those years.

[supereal]

59AB block in our shop. The owner wanted later distributor, thus the change in front. Note flat pistons.

[Seth Swoboda]

I've never used a flat top piston in a 59A or 8BA engine.

[flatjack9]

Originally Posted by supereal

59AB block in our shop. The owner wanted later distributor, thus the change in front. Note flat pistons.

What do the combustion chambers look like?

[fordscript]

Originally Posted by supereal

59AB block in our shop. The owner wanted later distributor, thus the change in front. Note flat pistons.

That engine looks like an 8BA to me....going by the enlarged water jacket holes at the rear, and the bell housing,(or lack of).

[Kahuna]

I'm with Fordscript; 8BA

[Seth Swoboda]

That's an 8BA block.