This is a rare Mazda Cosmo Sport Series I, just 343 of these were made and they were the world’s first mass-production sports car powered by a twin-rotor Wankel rotary engine.

The Mazda Cosmo Sport Series I

Upon the release of the Mazda Cosmo, Mazda would become the world’s most successful Wankel engine producer. Japanese engineers dedicated years to solving the inherent difficulties in the engine’s design and they solved them all one after the other – the only problem they weren’t able to solve was the emissions issue caused by the engine’s need to have oil mixed with fuel for lubrication.

By the standards of the late 1960s the Mazda Cosmo Sport had impressive performance specifications, the car was known as the Cosmo Sport 110S in export markets where it was greeted by an intrigued and oftentimes enthusiastic response.

Mazda Cosmo Sport Series I 13

The Series I Cosmo could reach a top speed of 115 mph (185 km/h), it managed the quarter mile in 16.4 seconds, and it could do 0 to 60 mph in 8.4 seconds. Power was provided by a twin rotor Wankel with a total displacement of 982cc or 491cc per side, the Series I version of this engine produced 109 hp at 7,000 rpm and 96 lb/ft of torque, more than enough for a car with a curb weight of 940 kgs (2,072.3 lbs).

Mazda spent six years working on the design of the Wankel rotary before it went into mass-production. A number of challenges needed to be overcome but perhaps none more so than the problems encountered with apex seals – no matter what they tried chatter marks would begin to appear on the inner walls of the rotor housing after a certain number of hours of operation – Mazda engineers called them the “nail marks of the devil“.

They finally struck upon a solution, new apex seals made using a combination of high-strength carbon infused with aluminum. This allowed engines to run for far longer with no issues, and it meant that Mazda could finally put the engine into production.

The Cosmo was always intended as a halo car for Mazda, as such they built them by hand at an average rate of just one per day over the model’s production run. The Series I was built from 1967 till 1968 with 343 made, and the Series II was built from 1968 till 1972 with 833 made.

Mazda Cosmo Sport Series I 11

Today the Mazda Cosmo Sport stands as one of the most desirable early Japanese sports cars alongside contemporaries like the Toyota 2000GT, the Datsun 240Z, and the Nissan Skyline GT-R. The rarity of the Cosmo and its historic significance as the first mass-produced twin rotor Wankel sports car have seen its values climb significantly in recent years with no signs of slowing.

The 1967 Mazda Cosmo Sport Series I Shown Here

The car you see here is one of the less common Series I examples of the Mazda Cosmo Sport. It benefits from a thorough restoration, it’s listed as having been well-maintained ever since, and it’s showing just 7,116 kms (4,421 miles) on the odometer.

RM Sotheby’s will be auctioning the car in late October with no reserve, the price estimate is $70,000 to $90,000 USD and you can click here if you’d like to read more or register to bid.

Mazda Cosmo Sport Series I 16

Mazda Cosmo Sport Series I 15

Mazda Cosmo Sport Series I 14

Mazda Cosmo Sport Series I 12

Mazda Cosmo Sport Series I 10

Mazda Cosmo Sport Series I 9

Mazda Cosmo Sport Series I 8

Mazda Cosmo Sport Series I 7

Mazda Cosmo Sport Series I 6

Mazda Cosmo Sport Series I 5

Mazda Cosmo Sport Series I 4

Mazda Cosmo Sport Series I 3

Mazda Cosmo Sport Series I 2

Mazda Cosmo Sport Series I 1

Images: Darin Schnabel ©2019 Courtesy of RM Sotheby’s

Founder + Senior Editor

Ben Branch has had his work featured on CNN, Popular Mechanics, the official Smithsonian Magazine, Road & Track Magazine, the official Pinterest blog, the official eBay Motors blog, BuzzFeed, and many more.

Silodrome was founded by Ben back in 2010, in the years since the site has grown to become a world leader in the alternative and vintage motoring sector, with millions of readers around the world and hundreds of thousands of followers on social media.

You can follow Ben on Instagram here, Twitter here, or LinkedIn here.


This article and its contents are protected by copyright, and may only be republished with a credit and link back to Silodrome.com - ©2020

Published by Ben Branch -
  Rennsport Porsche 911 ST