My uncle mentioned putting one in a car before and i have heard the term before. But i have never really known what it is. I assume it has something to do with the grind. just curious. Thanks for any help..

 

That's a new one to me.

 

i have heard of a 3/4 race cam......either way its old lingo

 

Ahh... the old 3/4 race cam. The stuff that the hot-rod equivalent of fish stories is made of. Everybody's secret 500hp recipe always included the much heralded 3/4 race cam. The last dip**** that started telling me all about his 3/4 race cam got quite a surprise when I told him that I looked at a 3/4 race cam, then decided on the 7/8 race cam for a little more top end. Confused the hell right out of him.

 

Either a really cheap one (less than a dollar), or one with only four lobes.

No such thing. Never has been, and probably never will be (unless you want to twist the terms around and rename one of the cams on a DOHC design V engine).

Jim is all over it. It is a term that is/was once loosely thrown around by those who had absolutely no grasp of the concepts of lift, ramp, duration, area under the curve, valvetrain accelleration rates, overlap, etc., and was a "red flag" used to identify those persons as such. I guess it still is being thrown around some of the Mopar circles, but from my understanding, those circles get a little messy in the middle...

EDIT: If you are planning to select a cam, you really need to study the data provided on the cam card from the manufacturer.

 

Nah, you guys got it wrong.

A 1/4 cam is whats leftover when you take a whole cam and make a 3/4 'race' cam out of it.

 

LOL, yeah I had heard people mention a 3/4 race cam before , but never of a 1/4.

 

Damn! If I'm not careful, I can learn something new every day....

 

Yeah, the conversation among the newbies with 6-cylinder 64 BelAirs used to go "Well, I got a ¾ race cam for my 283 I'm gonna build" "Oh yeah? Well I'm gonna have me a 327 and put a full race cam in it and then you'll see nothing but taillights"
:lala:

whatever {insert gender-specific self satisfaction gesture here}

 

Well it possibly could be as posted......in the days B.C. before computers in the last century, camshafts were "rated" at "xx race cams".......3/4 race cam was street/ strip, full race cam was just that....and therefore 1/4 race might have been a rather mild regrind.

ORRRRRRR.........who remembers Buz Shaller???

He "invented" the 1/4 speed camshaft.....but that wuz B4 my time.

 

Okay:
It seems that many think you are speaking of a 3/4 race camshaft. But, a "QUARTER SPEED" cam is just that, a camshaft that rotates 1/4 speed instead of 1/2 speed as most do, it had 2 lobes per valve. It was made by Buss (buzz?) Shaller of Shaller racing cams. he never worked all the bugs out of it, in that it tore up the valve train at high rpms. (remember this is the 1960's) Hot Rod did a big story on this back then, but as roller cam kits became cheaper and less prone to failure the quater speed cam just could not compete. It was tried in drag cars, A indy car, some super mods and sprint cars. Hope this answers your question.

 

Yea, the outstanding questions that exist in a 6 year old thread.
Nifty information anyway, but probably not relevant to any of these posters...

 

I finally found the answer.
It was a naming convention used by Crane Cams in their Wolverine Blue-Racer division.
Crane 103072 cam "282 HO8 3/4R cam & lifters"

It's a 282 duration hydraulic flat tappet.