With its undulating cooling fins, the 1969 Honda 1300cc motor is a work of art. Not only does wind flow over its airfoils, but through the engine as well. Much like the way coolant is funneled through passages in a normal engine, Honda’s Duo Dyna Air Cooling system used a crank-driven rotor to force cold air through the block.
Soichiro Honda was a genius, but also deeply idiosyncratic. Convinced that skipping the step of using air to cool fluid (which was then used to cool the motor), he browbeat his engineers into finishing this project long after they knew water was the superior technology. He wanted to compete against the Toyota Corona and Nissan Bluebird, but insistence on air cooling doomed the 1300-based sedans.
Still, if there was ever an air-cooled motor deserving of marvel, this is it. In the Honda 99S, the 1.3-liter unit it was capable of 115ps at 7500rpm — an amazing output at the time — with similarly impressive yet wholly traditional Honda rev ceiling.
This particular engine is on display in the Honda Collection Hall at Twin Ring Motegi. See more of our visit to the Honda Collection Hall in JNC #1.
Those fins aren’t that pretty, but I find the wavy lines strangely fascinating!
reminds me of my CF-48’s. 🙂 i love that engine and would love to have it in my living room as a conversation piece.. or a place for my cats to hide there toys..
Having worked in an iron foundry for years, that is one amazing work of art. The core work and molding! I imagine they only got one good piece finished for every 10 (or more) they tried to make.
Ferry Porsche would be proud. When did the 911 move to water? 1998? Still, a 911 engine looks like an HVAC unit, where Honda san’s looks like a work of art.
Wow, I’ve never seen anything like that. Tantalizing to look at.
To me this is beautiful in a pre-CAD, artist-with-pencil-and-sketchbook, sculptor-with-chisel kinda way. It strikes me as raw and basic but functional and ingenious.
It should also be said the car also featured a very large & heavily finned alloy oil reservoir separate from the engine which would also have been a crucial part of the cooling system.
Hey E-AT, my CF-48’s are currently in my living room!
The 1300 engine was a beautiful example of aluminum casting. I’ve always admired this engine (and CF-48’s) having designed a number of die cast parts over the years. Between the engine and the intricate shrouding, there are a considerable number of costly parts in the engine.
According to “Honda Motor: The Men, The Management, The Machines” the 1300 was a financial burden for Honda, and they lost money on each car sold.
The 1300 had a fantastic specific power output for its day – 100 hp and 7,200 rpm redline. The Duo-Dyna air-cooling system (DDAC) served the dual purpose of engine cooling as well as noise reduction. The inherent noise associated with air-cooled engines was a problem that Honda was trying to overcome.