I think this is a cool project. Plenty ambitious, but cool.
As much as we poke fun at these “tractor engines”, I’ve often wondered what would have been possible in terms of performance/ longevity/ economy if one could solve some of the inherent issues with Stovebolts:
* Crummy fuel distribution * Crummy drivelines they were used with * Pre-PCV blow-by covering internal parts with sludge.
Yes, they don’t flow air very well. They are heavy. But they are simple, rugged, well-balanced, and generate plenty of usable torque even as they are.
The driveline issue has been largely solved for those willing to do the T5 swap. Plenty of folks have created serviceable PCV systems for their stovebolt. Fuel delivery/ distribution seemingly has much room for improvement. Aside from the side draft YH setup that is unobtainium…and a few theories I’ve seen about custom manifolds with side draft motorcycle carbs….your project seems to be the most serious effort I’ve seen in that direction.
I suspect it isn’t going to create a practical solution for “the rest of us”, but I’m interested to see what you learn.
That’s a Thickstun or Thickstun-replica manifold. I’ve read that the theory with those goofy looking things was to equalize the runner length, but I’ve never read anything that proves any benefit.
Did you select the Thickstun because of the runner length?
The degree of atomization and droplet size has been tunable for many decades, it's what an emulsion tube (and its functional equivalents under other names) adjusts. In many carburetors it's a sized series of holes, which is why CFM is not a perfect comparator of accuracy on a different engine.
Vizard demonstrated that engines starved for air (low VE) produce more power with larger droplets, and engines with excellent VE do better with finer mist. The reason: a fully vaporized molecule of gas is 400 times the volume of liquid, and displaces air in the charge mass. The degree of vaporization also affects how mixture behaves in a manifold (fine mist has lower inertia), and at different vacuum and temperature levels.
The "Slant 6" intake runners are made in different length on purpose to broaden the torque range.
52 carl Just saw your comment about tractor engines,very true,I think they will run on coal oil too !! It is satisfying though to update to better stuff and get a durable,easy to work-on outfit.
