Where did that terminology come from? Was it a specific cam some certain company made like the duntov 30-30 cam?

I always hear the old timers throwing it around and know it was some kinda high performance cam but what were they running and calling 3/4 race cams?

not a "full" race cam but more than a "half" race cam

When people used that term back in the 80's , They would say "Yea ... my Nova has a 3/4 cam in it"

" Id say " Really ?? you have a .750 lift cam? "

This was with old school street racers - you know , 350 , slot mags , car jacked all up with air shocks, mullet , etc...

Goes back farther than I can remember. Flathead Ford days, and prolly into the 40's. Honest Charley asked if you wanted 3/4 race or full race cam. No other choices.

I always figured it was just a sales thing for people who did not understand camshaft timing specifications.

If your real serious you go 3/4 past full race.

I thought it was that you raced 3/4 of th time the time ,or full race cam strictly drag car with slicks and a double pumper carb
LOL DON

One of the first fiction hot rod car books that I read as a kid,(Before dirt was invented )was a story about two kids in the midwest in the mid fiftys that had model A and T Fords when they where in high school.One of them entered his car into a car show for a weekend, one of the other guys with a car in the show sold him and help install a Potvin "3/4" race cam for his 1948 Mercury flat head(they both had 1948 Mercs. in there cars) because the first guy had bought a "full" race cam from Potvin so he could go faster. As already said back then(when I was in Jr and Senoir high school) no one knew what the lift, duration, overlap or lobe centers where, let alone what that meant Lots of people "" " still don't I still have several of them "3/4" race cams that was ground last week by Comp Cams, do you want to race

OK....got the following info here: http://www.tildentechnologies.com/Technical/Take_34Race.html

What's a 3/4 Race Cam?

In the early 1950's the most popular original camshaft designers were the legendary Ed Winfield, the father of hotrodding, and Cliff Collins of Harman-Collins. If you look a Huntington's 1951 book you will find the specs for their cams listed. We've also listed some of their cams on our Flathead Performance Cams page. There were lots of cam grinders that copied Winfield and Harman-Collins cams, but these two were the designers and innovators in the early days. It was popular to refer to cams as a 1/2 Race or Semi grind and a Full Race grind. Later, there was a call for an intermediate grind between these two. To fill this demand, Ed Winfield took the intake lobe from his full race cam and the exhaust lobe from his semi cam and called it a 3/4 Race cam (see Flathead Performance Cams). It was literally half way between a full race and 1/2 race cam. Since that time, 3/4 Race has become a generic term for a high performance street cam, i.e. something less than a race cam.

Sounds pretty logical

Rickster

I have an old boy who works for me, he always tells me about his GTO with the 3/4 cam in it, one day I asked if it had a flat head Ford motor in it? he looked at me funny, I explained that terminolligy cam back from the flat head days.

A few years ago we built a poked and stroked flathead v8 and in our search for cams we cam across alot of listings for half race threequarter and full race cams.Used ede heads thickston intake and headers.2 stombergs mallory ignition.Neat engine.

It's what they use in the funny cars to run 1000'