Are flathead engines still made, well yes they are!
As everyone in the hobby knows flatheads were widely used internationally by automobile manufacturers from the late 1890s until the mid-1950s but were replaced by more efficient overhead valve and overhead camshaft engines.
They are currently experiencing a revival in low-revving aero-engines such as the D-Motor.
D-Motor is a technology company founded at the end of 2010 to produce and market engines that have been researched and developed over a period of many years.
Based on existing and well proven technology, our 4 stroke side valve (flathead) boxer engine was developed using the very latest technology including multipoint fuel injection, electronic ignition and liquid cooling giving a maximum continuous power of 93.68 HP at 3100 RPM (58 Kgs) for the 4 cylinder LF26 and 125 HP at 3100 RPM (78Kgs) for the 6 cylinder LF39. Combine this with high quality materials machined on the latest precision CNC machines, this ensures that crank shafts, connecting rods, camshafts and all engine parts are produced to the highest standards.

Our engines are most wanted for Helicopter and DRONE applications, because of their light weight, low consumption of MoGas @ 2.850 RPM, low RPM (Low noise) and performant nearly flat Torque capabilities continuously.
Sadly however…
D -Motor delivers engines ONLY to OEM aviation manufacturers.
But I guess if enough interest is generated, you never know!
Take a look at the D-Motor site here
Brand new Ford Flathead V8 engines were still in existence as late as the mid 1970s.
In 1972 I was stationed at Ft Dix, NJ. Just off base was a HUGE Military Salvage company run by a man called Lucky Mahalchic [not sure of his name’s exact spelling]. Lucky was one of those guys who was incredibly smart and bordered on insanity. He would only sell something [for cash] if he took a like to you. Lucky took a liking to me and allowed me to wander around the yard unescorted. I think part of it was I used to drive up in an old Packard, and he liked Packards.
I found a decrepit wooden warehouse filled with WW2 surplus items. Inside I found Packard Merlin engines and Packard M-2500 PT boat engines, all still sealed in their metal shipping containers. I also found 2, and possibly more, WW1 Packard-built Liberty airplane engines, but they were in an area of the building where the roof was leaking, and they were in bad shape because they had not been crated. I also found a fair number [probably several hundred] Ford flathead engines in wooden crates. Lucky refused to sell any of the Packard engines, but finally relented and let me buy a few of the Ford V8 crates.
So I found a barn in Maryland with room enough to store 15 Ford crates, and as I was vending Packard parts at the fall 1973 Hershey AACA event, I put 2 Ford V8 crates onto my little open trailer. I opened one crate to show what was inside [a complete engine ready to install, coated in wax preservatives]. Sold all 15 engines to a Ford parts supplier within an hour.
Probably sold them for too little, but I still sold them for 4 times what I paid for ’em. And I figured I could go back and buy more from Lucky. By that time I was stationed at Ft. Meade in Maryland, and when I returned to visit Lucky during the spring of 1974, I discovered the state of New Jersey had closed the operation down for environmental violations, and while Lucky was in Jail the state hired a big scrap company who sent it all for scrap prices, even the Civil War locomotive in the middle of the yard, and the 7 [yes 7] Goodyear blimps, all still unassembled and packed in crates.
Hi Bill, great story with a sad ending, but at least you saved a few! My friend was living in France a few years back and there were still brand new French versions of the Flathead V8 to be had, He brought a warehouse full back to the UK and they sold quick as you’d imagine!