When i was a kid I was told this a lot " it has 3/4 cam in it" small block Chevrolet of course. What is it ?
When i was a kid I was told this a lot " it has 3/4 cam in it" small block Chevrolet of course. What is it ?
Just a vague measurement of what kind of performance you can expect, equivalent to what they call "Stage 3" these days.
I thought it had something to do with lift and duration. .750 lift?
.750 = 3/4.
Way back I believe it was the cams between stock and full-race cams (not as much choice back then). At least that is what I have heard. Could also refer to a broken cam. 
Hot Rod or Car Craft had an explanation of this just a couple of month or so ago. Basically, a pseudo-race cam.
it's an outdated method of identifying which cam you have from back in the days when people didn't know or care about silly things like lift or duration and there weren't too many choices to pick from.
I always thought it meant it was 3/4 of the way to a full race cam.
It's missing a few lobes, hence the 3/4 designation. 
It's just what the kids who bought cars with lopey idles said because they didn't do any of the work themselves & didn't know the cam specs. I'm fairly sure anyone who has ever built their own engine has never used the term. It's something the wannabes used to say, like today's "nawwwws!" Morons who don't even know what a nitrous system is or what it does.
The explanation I always heard was: stock, 1/2 race, 3/4 race and full race cams. The more lift/duration/overlap, the closer to 'full race' it was.
At my dad's speed shop, we kept an old Chevy cam with 4 lobes cut off, when someone came in wanting a '3/4 cam' we'd plop that bad boy on the counter. The funniest part was some people would actually reach for their wallets...
Started in the days of flat head Fords, maybe even Model A 4 cylinders. There wasn't a real long catalogue listing for cams back then, so it actually made sense.
I didn't think that they used that term nowdays.
There wern't the choices that there are today.
Actually, for the neophyte it makes more sense then trying to make sense of lift, duration, lobe centers, overlap, etc.
My car is 3/4 race, so why should my cam be any different!
iceracer wrote: I didn't think that they used that term nowdays. There wern't the choices that there are today.
There have always been this many options. What there wasn't was the internet, so that everyone can gain a surface (mis)understanding of a complex subject and pretend to be an expert
It's for when you don't intend to finish the race. 
Ha!
you've heard of 1/4 Roy? Its like 3 of those, only replace roy with race.
C&P search...
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. 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.
Keith Tanner wrote: There have always been this many options. What there wasn't was the internet, so that everyone can gain a surface (mis)understanding of a complex subject and pretend to be an expert
You owe me a keyboard - funny because of how true it IS!
In reply to Keith Tanner:
Hey! I got all my misinformation about cams long before there was an internet
3/4 race cams are what a hot rider puts into his 350Z track car, duh!
If everyone is running a 3/4 race cam, I want a 13/16 race cam.
mistanfo wrote: 3/4 race cams are what a hot rider puts into his 350Z track car, duh!
Wouldn't that be a 19mm cam?
Make mine a 7/8 race 4/7 cam...
How about a 24/7 cam that works all the time the way you want it to...
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