Classic Hifi Care

The Hudson Hornet with it's big 308 cid flathead six was quite the machinery in its day.....

https://engineerine.com/classiccars/the ... m-1951-57/

Introduced in 1951 with a two-barrel single carburetor, it was rated at 145 horses, hence it's "H-145" nomenclature. By 1951, it was making 170 horsepower, via its "Twin H-Power" option, two Carter two-barrels. If we put this in prospective, the 1951 Buick 320 cid valve-in-head (OHV) straight eight only made 150 horsepower. The 1952 Buick 320 with its four-barrel carburetor finally made 170 horsepower. The new V-8 in the 1953 Buicks made 188 horsepower with four-barrel carb. In 1954 it made 200 horsepower, 1955 saw 236 horsepower, and by 1956 with AFB carb, better breathing, larger valves and hotter camshaft standard, the Century 322 made 255 horsepower and was faster and lighter than the Hornet. In 1954, Hudson introduced the 7-X option with featured thinly disguised racing parts such as higher compression, hotter cam, dual exhaust and made 210 horsepower.

Hudson dominated Nascar during 1953-54 thanks to tuners like Marshall Teague and Smokey Yunick. Oldsmobile was their chief competetion. It took the 300-horsepower Chrysler Hemi in 1955 to finally derail the Hornet six. The step-down Hudsons were campaigned successfully in NASCAR during the 1950's. In 1955 the "HASH" was a Hudson badge on a Nash body, less aerodynamic and heavier than the old step-down bodies. The Packard 320 V-8 was an option in the 1955 Hudsons and was a slug compared to the six.

The Olds 303 started out in 1949 with a two-barrel carburetor and 135 horsepower. In 1952, it got a four barrel and up to 160 horsepower. So we can see that the OHV V-8 still didn't put out the power of Hudson's flathead six. The base version of the Hudson 308 came with 145 horsepower. I reckon the fact that Oldsmobile was competetive at all against the Hudson six was an accomplishment in itself. The downside of the Hudson six was its proclivity to use oil, sometimes massively use oil. And the cork clutch, which was a nasty job to replace. The high-chrome-content block was so hard rings wouldn't seat if the engine wasn't driven hard.

So why would a flathead 6 have such an advantage over OHV V-8s, which have several theoretical advantages--breathing especially? In the case of the Hudson, was it just bright guys deploying cams, compression, and carbs?

Chris Campbell

That is a question for the ages, Chris and the reason for my post. How did Hudson run high compression, maybe close to 10 to 1 when flatheads were not given to "holding" or "sealing" well under high compression. What would have happened if Hudson had used supercharging on the 308? That might have been a monster! Or a mess. Witness the lackluster performance of Kaiser when they supercharged the Continental F-226 used in their Manhattan series of cars. The F-226 was a competent industrial engine, but only made 140 horsepower supercharged. Added to a Hydra-Matic drive, you can imagine that they were not peppy cars. It was 226 cid versus the Hudson's 308, but it should have done better than it did. Why couldn't Chrysler make that kind of power with its excellent line of flathead engines, both six and straight 8's. The early 331 Hemi V-8's couldn't outrun the Hudson six! It took the dual four barrel carb 354 at 300 horsepower to finally knock the Hornet off it's perch in NASCAR. The 308 was a bored and stroked version of their workhorse 262.

As to the side valve versus overhead valve comment, let me say this. In all versions of the flathead 308 it put out more power than a Buick OHV 320 straight eight. It held its own with the newer 322 V-8's until the souped up 1956 models came out. They had bigger valves, hotter camshaft and different manifolds with dual exhausts for better breathing, yielding 255 horsepower. This engine, properly tuned, could arguably better the newer 364 cid version for 1957. Yet it took a "hotrod" Buick OHV V-8 to be able to take the Hornet six.