Hi everyone;
I recently aquired a 49 Dodge Power Wagon with the 230 six, and was thinking about transplanting a SBC to get a cruising speed compatible with today's secondary road speeds (50-60 mph). However, after doing more digging, I'm thinking about triple carbs, a tri-Y header, and 4.89 diff gears.
A few of the people on the Power Wagon Advertiser BB have made up intake/exhaust manifolds using different carbs (Rochester or Holley 2BBl) and have seen surprising results. One fellow had access to a chassis dyno, and saw a rear wheel Hp increase from 45 to 65!http;//www.powerwagonadvertiser.com/forums/showthread.php?t=4848 Another adapted a Jeep exhaust header (same thread, see pictures), and noticed "blue jean dyno" improvements in not having to downshift for hills, and being able maintain 55 mph road speeds. I had wondered if the rods & crank would last much beyond the 3200 RPM governed limit, but Hudson's experience shows that they can.
The "hot oil, cool water" issue bears further investigation. Some very odd things happen in engine cooling passages! The late Smokey Yunic found that water would flow alternately between one head and the other due to steam pockets in the small block Chevy. The water in Hudson's engine may not reach the hotter parts- which might explain the high oil temps being reached in a very short time. I would monitor oilpan temps, and if they are over 200 deg, I would run an oil cooler, and start working on a pressurized cooling system with a crossflow rad. A full synthetic oil would also help. A method of running a full-flow oil filter on the flathead is shown at
http://t137.com /archives/wwwboard74/messages/74015.html ,it could also take a cooler. There is a plug between the two hose fittings in the oil pump inlet galley, oil from the pump flows thru the first hose to the remote filter, and back into the engine thru the second fitting.
David Vizard mentions a triple SU carb setup he did for a 6 cyl LandCruiser in his "Carburetors & Intake Manifolds" book that added 30 extra HP, a glass-smooth 450 rpm idle, and "steam engine torque" to the low end- the engine was unstallable. His other experiences with V8 individual carbs have been impressive- 70 lb/ft gains in torque, 50 extra HP, better fuel mileage. A friend of mine who ports heads for a living has been simulating his 300 CID Ford on the computer with headers and triple Mikuni 44's- the computer says it will be an animal. The Mikuni is a widely used snowmobile/motorcycle carb- very tunable, and inexpensive compared to Webers or Dellortos.
I don't know how closely the results with OHV engines will translate to flatheads, but judging by the way it responds to Rochesters/Holleys, better mixture preparation should make a noticeable difference.
