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I have a question. I was reading Bob Turnquist's book and the chapter I was reading (10) talked about the change from babbitt to insert bearings.Bob stated that some 11th series engines were equipped with the new insert bearings and that the entire line went insert for 1935-also that replacement connecting rod bearings with inserts were made available for tenth and eleventh series cars. My question was this a no-cost upgrade for the Packard owner of an tenth or eleventh series car owner and two is there any idea what percentage of these engines were upgraded?

I've also read that in Turnquists book; I've wondered about it; as wonderful as the book was at the time, it has MANY statements later found to be incorrect. In my own experience with 1934 Packards the only ones I've ever seen that appeared to be unaltered since built that had insert rod bearings were very late-numbered Twelves. I'm familiar with several VERY LATE Eights that had babbitt rods. In the 60s and perhaps before, while the insert rod bearings were still to be found (though never plentiful), some owners of earlier cars bought later rods built for inserts and installed them in 34 and earlier engines. But then the supply of insert bearings dried up (by the early 70s and we saw the opposite often happen, folks with the 35 and later engines were seeking earlier rods from the babbitt era to bring an engine back into service.

After the switch-over, factory-rebuilt engines from the babbitt era were probably done with insert bearings and corresponding rods, though babbitted service connecting rods remained as service parts for some time after the changeover.

I doubt any engines were upgraded by dealers just because the owner wanted a change (and if so, certainly not for free); more likely it occurred when there was an engine bearing failure.

could I talk to you in the chat room?

Got a phone? It's much easier. PM sent.

One more question-if I decided to have the 1934 Super 8 converted to run with inserts (assuming my effort to acquire the car is successful) how much labor would it be to have the job done? Meaning $$$$.

It depends a bit on what kind of driving experiences you anticipate. Lots of approaches have been tried, some successful, so not so successful. Remember that babbitt is very protective of the crankshaft by its ability to embed small particles; the journals were shot-peened before final machining in the babbitt era, but also hardened with the adoption of inserts. Also the original inserts were flanged bearings and the sides of the flanges were also babbitted to ride against the cheeks of the crankshaft and determine rod end-play. The conversions I'm familiar with (I'll attach an old CCCA article though other conversion ideas have come along later) use brass weld buttons on the side of the rod to make up the space. Also some of the conversions require notching of the rod bolts - again something that doesn't sound like a good idea. One advantage to babbitt is that it can be finished to any diameter required - for example if only 0.003 was required to bring journals back to true, then you just sized the babbit to that undersize rather than jump to 0.010 or 0.020 or whatever the next undersize insert was available in.

Keeping engine speeds within the original design limits should give babbitt bearings a life of 80,000 or more miles, sometimes many more - heat (from high engine speeds) is the major enemy of poured bearings and Babbitt became problematic as roads improved the opportunities to drive faster became more common. A couple of prestige restoration shops that I'm familiar with that restore these engines, not just for show but for touring, stay with poured bearings on engines that were originally done with Babbitt. My own 34 Eight went 83,000 miles before I finally heard my first hint of a rod knock and decided to rebabbitt - that's not much less (if any) than the life of the inserts - again assuming you drive at speeds that are consistent with the conditions of the time. If you're going to install a high speed rear and plan on a steady diet of 65 or more mph, then I'd give a conversion some serious consideration, otherwise not. Another factor to consider is the cost of removing and reinstalling the crankshaft counterweights if the journals need resizing - its necessary when doing babbitt as the bearing surface is the full width of connecting rod big end; the inserts when done by Mr. Shower's method have a smaller (narrower) bearing width and apparently you can get away with not resizing the full width of the crank journal and hence not removing the weights.

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