HELP NEEDED!! Hot Rod'n a 37 Hudson 8 cly

A bit more history!



The 1940 Hudson Eight sedan did slightly better than the 1938 model by travelling 1,000 miles at 91.34 mph under AAA Class C scrutiny.

Yep that is the rare Edmunds Hudson 8 intake! Any idea what it went for?

It's a well established fact that the original rods were extremely good quality, due to the fact that the babbit metal was centrifuged in, giving a dense grain. Of course everything was very strictly controlled as far as babbit material and temperatures, and of course they did thousands of these at a time, and probably bought a lot in as well. From time to time you see original rods for sale on ebay, but usually broached to standard size, and of course these are not much use if your crank has been ground. I'm no metallurgist, but I do know that poured rods do not have the density of grain that a spun bearing has, plus there are variations of temperature, babbit quality, tinning of the rods, etc. etc. that all combine to affect the quality of a re-done rod. It has certainly been my experience of re-babbitted rods that they seldom last longer than 40,000 miles before breaking up, especially on the earlier Essex and Hudson super six rods which had real thick babbit. I would use a set of used rods with good babbit rather than have a set re-done, if I have a shaft that can be ground to the same size, my theory being that if they have stood up thus far, they should be good for a while yet, and so far have been proved right. I have had many failures of re-metalled rods, but none with good used rods. The main bearings in my '28 Essex were good used ones which I installed in the motor and then had the shaft ground to fit. nearly 100,000 miles later they have not been adjusted, and are still quiet. I rest my case! As far as converting to shells for the con rods are concerned, I have experimented with this, and it can be done successfully retaining the splash feed. I used Continental C4 rod shells ( they use this engine in Clark Forklifts), and I know of others who have used Mark 1 Ford Zephyr shells, and Willys Jeep shells. Be careful though that you use white-metal shells, as some modern shells are far too hard, and will wear the crankshaft rapidly. You must give good oil circulation, by cutting a spiral groove that circulates the oil right across the bearing.



Geoff.

Stepdown James wrote:

Geoff, I certainly appreciate your taking the time to share your experiences with babbitt rods. I would like, however, to ask a small clarification from you, if you don't mind. Please forgive me if I seem a litttle bit slow as I am, simply put, a little bit slow. Using my crank ('50 C8--94,000mile) as an example--It has standard journals and fortunately looks as though it would only require a light grind to clean it up nicely. Are you suggesting that I locate used oversize factory Hudson rods (from an engine that had a factory undersize crank) and have them honed out to match whatever my crank turns out to be? I know that when it comes to grinding cranks people speak in terms of even numbers (0.010", 0.020", etc), but in a case where one were to hone out excess babbitt material from a rod perhaps it's OK to think of taking a minimum of material off of the crank? Lastly, I've accumulated a number of remanned rods from aftermarket sources like Thompson, Federal Mogul, etc. Do you think there's any reason to beleive that they are any better then those that a fellow might send out to a local machine shop to have poured? Any further thoughts you or others might share would be greatly appreciated!

James

As far as I am aware, all the factory and other suppliers ( e.g. Federal Mogul) rods are of equal quality. These were all produced in approved machine shops which had the facility to centrifuge feed the white metal. If you have a supply of these undersize rods, then you are far better off to get the crank machined to the size of the rods. Factory rods are usually more precise than poured and rebored rods. I don't want to offend any machinists who may be reading this thread, and they may disagree with me, but I am going from my experience here in New Zealand. We kept cars going for much longer here than back in the states, and many places did re-metalling, but only a few excelled in the art. We did have a local shop had a centrifuge, but when the owner died the skill died with him. I'm not an engine reconditioner, just a self-taught backyarder who has motored and maintained H.E.T. cars for 50 years. When I did my Essex motor, the main bearings were in the block, and in perfect condition, but I did not have a crank for it, so I selected the crank I had with the biggest journals, and had it machined down to fit the main bearings. Unfortunately, the rear journal was already .010 under the size of the bearing, and luckily it was only half a thou out of round. So I removed the main shells, and packed it right around between the shell and the block and cap with .005" shim steel, filed the butt edges of the shells so they had just enough crush, and re-installed, much to the horror of the machinist! This effectively shrunk the inner diameter of the bearing .010" all round. It is still in there! It is much cheaper and easier to get a crank ground than to bore out rods and line-bore main bearings. As a side-thought, I wonder why Hudson used stepped sizes for the main bearings. It really is a pain when it comes to machining! Good luck,

Geoff.

Park W wrote:

I can confirm the comments on benefits of a more open exhaust system. I ran a home-made split (dual) exhaust manifold on my '38 H8 back in '53, starting from when I first got the engine from the rebuilder (who ran a splasher 6 '38T coupe and a splasher 8 37H coach on our local track). In the 3300 lb. '38 sedan I had, it ran 17 second quarters at 84 mph and would beat any new Olds 88 from a traffic light or on the strip. I never realized how much of its performance was from the dual exhaust setup until I had an occasion to temporarily replace it with a single. The difference was dramatic. I've not seen any mention of "re-profiling" the coutour of the bottom of the lifters. That was a trick known by Jack Clifford as well as my engine builder in '53. The idea is that you flatten out the curvature quite a bit. Makes a notable improvement in power. Of course a 3/4 grind of the camshaft would be even better. By the way, at the drag strip (near Chicago) we disconnected the regular exhaust pipes at the manifold outlets and connected a couple of short flex sections that emerged under the RF fender, just behind the wheel. Sounded damned fierce, I'll tell you!

According to a couple of calculators on the web, to shift 3,300 lbs to 84 mph trap speed over the quarter indicates flywheel horsepower of 151! In fact to get that heavy car up to that speed over the quarter is quite an achievement for what I assume was a fairly stock eight apart from the exhaust.