How the Small Block Chevy engine dominated the Hot Rod world
Hero photo by Kevin Butz on Unsplash Text and errors by: Chris Breeden
Have you ever heard of the “Duntov Letter”?
Here’s a little background information if you’ve never heard about it: In 1953 Belgian 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 Corvette’s top speed through mathematical calculations, a real slide rule resume. In December of ’53, Zora sent 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:
Ford is dominating the Hot Rod world. While no car manufacturer 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.
In order to attract interest in the new OHV V8’s, Chevy could offer speed equipment over the counter, as upgrades for the Corvette.
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 Vinmotive.com vast historical archive.
“…FROM COVER TO COVER, THEY (HOT ROD PUBLICATIONS) ARE ALL FULL OF FORDS.”
Point 1: Ford is dominating the Hot Rod world
To test out this statement I consulted Vinmotive.com’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 Vinmotive.com vast historical archives.
“… 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.
(Left) Small Block Ford engine (Right) Small Block Chevy engine. Both engines are facing each other. This demonstrates how the front mounted oil pump of the Ford interfered with the front crossmembers in early cars. The Chevy’s rear mounted oil pump was, and is, perfectly designed so as to not interfere with cross members when installed in early Hot Rods.
“… 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.”
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