It was invented by a rail drag racer named Ollie Morris and was called Ollie's Cam-a-go and was made and sold by offenhauser company in Los Angeles . It mounted in place on the timing chain cover and manual and automatic units were available. By changing a setting the cam position could be changed by 10 deg.either way The manual had to be adjusted under the hood and the automatic could be adjusted via a cable while driving. Both were adjustable with the engine running. There was another company out there making Variable Cam Timing gear sets called Veri-Cam I believe
That's pretty cool tech. How durable were these setups? Ollie ran a very cool car back in the day called the "Smokin' White Owl" Can't find the picture right now.
This is something I would buy if Offenhauser could remake any past part. I wonder what engines besides SBC it was available for? New engines are now making use of this technology. Something like this might make a difference in the Engine Masters. A win would be more advertising than Offy has had in the past 30 years. I hope that other thread hurries up with a PDF catalog as it's the non intake Offy products that spark my interest.
That's odd, Dan ( Dmarv) the HAMBer that started this thread is Ollies grandson and only a few days ago was looking for the car . http://www.jalopyjournal.com/forum/showthread.php?p=1014503#post1014503 In fact that 606 in his Avatar is the race number from the side of the Smokin' White Owl.
I was intrigued by the Vari-Cam deal when I saw old ads for it in ancient mags. I asked some veteran engine builders about it and they all shared some similar sentiments. Firstly, it did work as a way to vary cam timing while the engine was runnning, which was the intent. The problem was, this naturally alters ignition timing too, since the distributor runs off the cam. There was no provision to synchronize distributor timing with the cam timing. This is why I beleive it never showed up in the Engine Masters competitions, which I had a hand in creating. Also, there were durability issues. The VariCam was known to fail, and it'd usually alter the cam timing enough after failure to ruin many other parts. The way to do this on a modern engine would be through electronic controls. Modern engines don't rely on the cam to drive the distributor. A cam position sensor triggers the spark (along with input from a crank trigger). These could be manipulated in software to be synchronized. However, to my knowledge, no one has done a retrofit package or developed any type of functional equipment along these lines. The VariCam was a mechanical system and had its limitations because of that. Its sort of like comparing mechanical injection to EFI or mechanical timing advance to electronics. Yes, the old systems worked, but nowhere near as well as the new versions. The only glitch is that no one has developed a modern version of the VariCam as yet. The variable valvetrain and timing systems mentioned are the closest thing. Should this technology be revisited, accounting for distributors driven by these same cam gears you're moving around would be paramount. Durability would also have to be delivered. One more thing we have today they didn't have when the VariCam was being sold is lawyers who would sue for the cost of the engine(s) damaged by a faulty part sent to market. Neat idea, but one requiring further development in a more-modern package. ~Scotch~
Man! How did I miss that? Welcome! I'll bet your grandpa has some great stories. I got some videos of old races for christmas some years ago that include footage of him making some passes in the owl. If you're interested I'll find the names of the tapes.
It looks to me like the automatic version uses oil pressure to retard the cam. Since that should be fairly linear with RPM it shouldn't be hard to add more advance to the distributor to comepensate. I would assume the retard tip in point is also adjustable so there would be a little work at the start of the curve, but certainly possible. No crank triggers in Engine Masters this time around.
You make it sound so simple...LOL! Actually, you've made it obvious to me you understand exactly what is going on and what needs to happen. Yes, it's all possible and doesn't seem like it'd be that hard to engineer. Still, I've never seen anyone try with any level of success. The closest I've seen to a modern version of this was in the first Challenge. A guy from maine used a belt drive and installed a tensioner on a stepper motor. The idea was to shorten the belt with the tensioner in measured amounts and alter cam timing in conjuntion with with rpm. It was simple and sounded good on paper, but when he tested it prior to the competition it made no discernable power gains, since the amount of camshaft timing alteration was relatively trivial. It just didn't have enough travel. Neat idea, though. I prefer your method and I've got one more I'm working on myself. I can't say too much about it but I have a pretty good idea it'll work. We'll see. Let me know if you make any progress on this. I'm more than a little interested. ~Scotch~
Don't shoot me for asking, but how does the Honda Vtec work, and could it be adapted to a traditional V8?
Here's a how-to on the VTEC: http://www.leecao.com/honda/vtec/index.html It's a 4-valve deal, and the second set of valves open only when they're needed. 2-valves down low, 4-valves up high. Not an easy adaptation to existing or vintage 2-valve engines. ~Scotch~
Okay- Can we shoot you yet? Seriously, the adaptation deal is a tough call - it'll never be simple. There are OHC and 4-valve kits out there for the SBC, but they're pricey and some have proven unreliable. Personally, I feel the future lies in camless technology, which exists and could be retrofitted. Check out www.sturmanindustries.com and http://www.sturmanindustries.com/main/flexibleCharts.htm Sturman's deal is the best for several reasons. First, they open and close the valves with hydraulic pressure, and the opening and closing are controlled by independent solenoids. This means they can alter when the valve opens, when it closes, and how much. They are retrofitting this on big diesel trucks now, and cars are in the future. This "camless" technology means you can have a smooth idle and high-lift/long duration at higher rpm. The unlimited nature of the valve operation means you can program in the optimal valve events for any potential situation, much like EFI controls fuel and spark now. It's real, it works, and it's the future of the piston gasoline engine, in my opinion. I only wish you buy stock in Sturman Industries. If they don't do it themselves, their designs will inevitably be used in some form by the OEMs. Cams will go the way of the Flathead and the carburetor. This is just SO much better, and it doesn't lock you in to one single lobe pattern like a cam does. There are less parts than a VTEC setup, and multiple valves are not required (although they'd work well with this system too). I also like desmodromics, but this requires precious space under the valve covers, which few vintage engines have. The new Ford "modular" family of engines is OHC, and may be a candidate for desmo, but I haven't looked too far into it. The existing variable valve timing systems (along with the "displacement on demand" systems being offered by others like Chrysler) show the future. Using less engine when its not necessary, but having more displacement and flow "in reserve" seems to be the way. Electronics will control all of this based on engine load (vacuum) and throttle position. If you really want a good peek at the future, and a chance to corner the market on hot rod retrofits, start investigating CVT transmissions... If you start whittling adapters now, you'd be SO cutting edge by the time people figure out how awesome the CVT design is. Combine a couple of these technologies and you'd really have something. A "camless" Hemi backed by a CVT would truly be revolutionary and amazingly practical without WOT performance sacrifice. Do all this and I'll "test" the products on your behalf. I'm a giver like that. ~Scotch~
do you know if the manufacture of the varicam is still in business.i have one.i want to say it is a prototype.
a popular VAR-I-CAM that was employed on many drag race engines actually employed a spring that would hold it to a predetermined point, and then as rpm increased, the cam would change. this, along with a variable bleed down hydraulic lifter, (RHODES LIFTERS) was a real giant breakthru in the cam speck limited classes at one time. I remember quite a few engines that would really rattle when the driver would let off at the end of a run. VAR-I-CAM was built and sold in SAN DIEGO, Calif.....circa '60's.....
I'm surprised Cob hasn't chimed in with a rant by now about variable valve timing, the V-Tec scandal and his Corvair engine prototype and reverse flow SBC...
V-Tech explained; http://i270.photobucket.com/albums/jj105/alpina2-7/v-tech.jpg It works on an oil pressure/rpm bases. It uses all four valves all the time but in the v-tech mode uses a second lobe on the cam ( much more agressive ) to control the valve action. It works very well.
As far as I know there has never been a camless F1 engine that was actually used in a race. For many years now they have used pneumatic cylinders in place of valve springs because conventional springs can't react fast enough at the very high RPMs they run (18,000+) There has been experimentation with camless engines, primarily using electromagnetically actuated valves, but it has never been put into use. There was a company called Aura that was working on a camless engine and had a running prototype based on a 2.3L Ford engine. It's an interesting concept. If the valves were electronically controlled you could have infintely variable valve timing. If you had a system where the valves, fuel injection and ignition were all computer controlled you could have an engine that could self start without a starter motor, shift the power and torque curves on demand, shut down cylinders in cruise mode, all kinds of things. Kurt O.
a way out thought on the camless concept is what was developed allready by using a number of nozzles to shoot/inject air into combustion chamber and then shoot in a fuel source and then combust. then the piston uncovers a seperate "window" to have exhaust.
The 2-stroke window style exhaust makes for a very dirty combustion cycle unless you're also using the air nozzle to clear the cylinder...also I'd think the exhaust port side of the cylinder wall would wind up losing oil coverage...personally, I'd rather see a solenoid activated port valve (like a rotating ball valve style port or something)...that way you clean up a hemi style combustion chamber with 3 ports and a spark plug...in all honesty, it'd be simple to inject the air via A/C style air pump creating pressure for the system, inject fuel via conventional port injectors, and exhaust via solenoid actuated valve...the trick would be finding components that could handle the heat and compression of being mounted directly to the chamber...
The Jalopy Journal
