Anyone remember the Schaller(sp) quarter speed cams? I don't remember exactly how they worked or when they were sold. I think they were made for small block Chevys.
We had a thread about them here years ago. I was trying to find history of a local drag car that was sponsored by them. A HAMBer is resoring the car, it is in the drag car thread.
That picture ****s because when I took the picture I had the crank gear on top of the cam gear. I looked for about 8years for a complete Schaller cam kit when I finally found one on ebay.
I remember the Schaller cams from back in the day. I was reading Hot Rod cover to cover and getting my feet wet in engine stuff. What it boiled down to was there really is no advantage. Yes the cam turned 1/2 the normal cam speed (1/4 crank) but since there were 2 valve sequences for each revolution the valves still operated the same. The one disadvantage is that lift and for that matter the whole lobe profile was very limited due to there not being enough room on the cam core to get a real performance lobe shape. Looked cool as heck though...I'll grant you that!!!!
Wrong...Actually there was plenty on the cam core because it was a billet cam not a cast piece. As for the (real performance lobe shape) put a degree wheel on one and you will understand why it is shaped that way 1/4 speed... The real disadvantage was price$$$ and the fact that Schaller p***ed in '67 I believe. I not starting Drama I promise.
I just came across an article in an old HRM about the Schaller Cam Special Fiat Topolino...up until this thread I'd never heard of them...I'd love to hear one run, just to see if it has a different sound to it...I'm surprised that the design wasn't pursued more, since your cam would run slower and produce less friction/drag on the motor...seems like a solid concept to me...
Wrong...Actually there was plenty on the cam core The lobe cannot be taller than the bearing journal, unless you saw the engine into chunks, so that that big lobe doesn't have to p*** through those tiny, whattya callem, cam bearing things.
Its an interesting conundrum. Yes, the cam surface speeds are lower, but the cam has to lift the same amount in the same amount of time, meaning the pressures on the lobe will be higher. I suspect the resulting gain is zero, sort of like what happens when you increase a bearing journal diameter. But it would be interesting to know for sure. One thing we know, MT wasn't afraid to use new stuff that worked. Makes me wonder... Bill
Hmmm, the cam profile must ramp pretty fast compared to a single lobe profile, just to get the valve events timed properly at half the cam speed...very very interesting stuff...I'd still love to try one in my Pontiac motor...I doubt very much money went into R&D being it was built by a small independant manufacturer, so it's interesting to think of how many various profiles he offered and how he figured out the profile for half speed...
I'd think it'd float just as bad since a twice as radical ramp on the lobe running at half speed is just as likely to cause valve spring issues at high RPM...but that's just my understanding of what's going on, I don't know for sure that's what's going on...
The Jalopy Journal
