- Hero photo by Alex Read on Unsplash. Art, text and errors by: Chris Breeden

Hot Rods, overhead valve V-8s, internal memos & a Belgian

How the Small Block Chevrolet engine came to dominate the Hot Rod world

Have you ever heard of the “Duntov Letter”? Here’s a little background information if you’ve never heard about it. In 1953 Belgian born Zora Arkus-Duntov, designer of the Ardun OHV (overhead valve) conversion for the Flathead Ford V8, went to work at Chevrolet as an assistant staff engineer. Zora first witnessed a Corvette at an Auto Show in late ’52 & was so impressed with the car he wanted to go to work for the company that produced it. To get the job, he sent Chevrolet a letter in which he accurately determined the Corvettes top speed through mathematical calculations, a real slide rule resume. In December of ’53, Zora sent to his boss, Maurice Olley, The Chevrolet Motor Division’s Director of Research & Development, an internal memo that many people say was the blueprint for how Chevrolet would go on to usurp Ford in the Hot Rodding world. The memo, entitled “Thoughts Pertaining to Youth, Hot Rodders and Chevrolet”, mainly boils down to the following 3 points:

1. Ford is dominating the Hot Rod world. While no car manufacture is currently selling new cars to Hot Rodders, one day these Rodders will be able to afford new cars & they’ll stick to what they know & right now all they know is Ford.

2. In order to attract interest in the new OHV V8’s, Chevy could offer speed equipment over the counter, as upgrades for the Corvette.

3. These upgraded parts would increase power numbers, but would not affect reliability.

Let’s take a look at these 3 points:

Typical Advertisement found in Rod & Custom magazines during the time in question. From the Custom & Hot Rod Life vast historical archive.

Typical Advertisement found in Rod & Custom magazines during the time in question. From the Custom & Hot Rod Life vast historical archive.


Point 1: Ford is dominating the Hot Rod world

To test out this statement I consulted the tribe’s vast historical library from prior to December 1953. I found, in Rod & Custom magazine, from its first issue in May to the November issue there were a total of 56 ads. Of those 56 ads, 14 of them were for parts & accessories specific to Ford vehicles. Not a single ad for Chevy parts & accessories was to be found. The only ads for specific engine parts were from Navarro Racing Equipment & they were for Ford & Mercury heads & intake manifolds. While a number of Chevy cars were found featured in the magazines, these where for cars that fell squarely into the Custom category & not Hot Rods. All of the technical articles were about generic modifications that could be done to any engine, but the implication was they were to be done on Flathead Fords. OK it seems Zora has a point here.

From the Custom & Hot Rod Life vast historical archive.

From the Custom & Hot Rod Life vast historical archive.

“… The potential of our RPO V-8 engine is extremely high but to let

things run their natural course will put us one year behind and then

not too many will pick Chevrolet for development…”

Point 2: Attracting interest to Chevy's new engine

Zora argues here that the natural curve for finding out what will and will not work on any new engine for a Hot Rodder is about 3 years. Since Chevrolet was coming in last with their new engine, this would be something that Chevy would never overcome. After all, if everyone has figured out the Caddy, Ford Y-block and the Chrysler Hemi engines, why would anyone want to waste their time on figuring out the Chevy? Especially considering, that no one had ever thought about Chevy as a performance name before. The twist in all of this was what If Chevy did all the figuring for them & then sold the parts over the counter at the local car dealer, this would be a huge step towards allowing Hot Rodders to experience what Chevy had to offer. All right, Zora’s a pretty sharp guy. I’m starting to see why they gave him a job.

From the Custom & Hot Rod Life vast historical archives.

From the Custom & Hot Rod Life vast historical archives.

“… The task of making (the) powertrain reliable is therefore easier…”

Point 3: All of this with no ill effects

I believe this last point is to address the concern of high horsepower engines being prone to breaking. I think that Zora feels the need to write these few sentences on the subject because he knows if he doesn’t he’ll be questioned about it. I think he knows that the reliability will be built into it. In other words, Chevrolet wasn’t going to sell a cam shaft capable of damaging the engine. They were going to think out what they were going to offer. That Zora was one smart cookie!

This memo is an example of a pretty interesting piece of automobile history, but I don’t think it should be taken as Chevy’s blueprint for taking over the Hot Rodding world. The real blue print was the one for the SBC engine. Regardless of this one memo, Zora Duntov & Chevrolet changed the Hot Rodding world just by engineering and selling the SBC. It was inevitable the SBC was going to become the new choice for Hot Rodders because of its rear mounted oil pump, part interchangeability between models, low cost, durability & superior design.

You can find images of the 3 page memo at the end of the article & please remember: “These thoughts are offered for what they are worth: one man’s thinking aloud on the subject.”

Keep on Cruisin'!

Art by: Chris Breeden

Art by: Chris Breeden

About the Author:

"Chris Breeden is a Social Media content creator for Custom & Hot Rod Life on DRIVETRIBE, YouTube and Facebook. After spending 5 years in Southern California, a.k.a. Hot Rod Heaven, while serving as a jet engine mechanic in the United States Marine Corps, he moved back home to Tennessee with an even greater love for Hot Rodded Vintage Tin. Since then he has worked in retail sales and the transportation and logistics industry. In 2018, seeing a gap in Hot Rod and Custom Car coverage on DRIVETRIBE, Chris began advocating for their inclusion on the platform. During the summer months, he can be found all over the Tennessee region covering car shows, meets, and cruise-ins. During the winter months, he can be found in the garage working on his custom 1949 Ford two-door sedan and 1954 F100 truck."


Join In

Comments (0)