Packard Forum Index » Post-War (1946-54)

Quote:

From seeing many engines come and go through a machine shop and having first-and experience with machining, I'm going to respectfully disagree with the above statement.

1. The Packard block cast iron alloy is not appreciably harder than other makes cast iron. This urban legend comes up in most antique car web sites. We've had Hudson, Studebaker, Oldsmobile and many other old makes quote the same misinformation; many actually disappointed we aren't going to charge them more to bore and hone their "high nickel" block.

2. Stainless valves will not protect the exhaust valve seats against erosion. How long the valve seats will hold up depends mostly on how many highway miles the engine sees. A hobby car getting only a few hundred miles a year will probably last forever. One which is used for long distance touring eventually needs hard exhaust seats.

3. Properly installed hard exhaust seats in a properly tuned engine aren't likely to fail. The only time I've ever seen a problem is when incorrect ignition advance, clogged radiator or stuck thermostat, caused severe overheating to the point everything on the top end was damaged.

Your opinions and results may vary.

jack vines

If memory serves only a few years back their was an article in the Cormorant Showing old ads comparing the Packard block with a Chrysler block. The Chrysler block had inserts (low Quality Cast Iron.) Versus the Packard Block ( High Quality cast Iron.) Didn't need Inserts. I only point this out because Packard themselves made this statement. Not urban legend. Is it true? I don't know. This was pre war too. Did this change after the war? Again, I don't know. But why would Packard make the claim if not true? Seems to me to be a lawsuit in waiting if false. I don't doubt anyones experience. And if people in the field don't see a difference.I don't doubt that. But, then What gives with the Ads that make that statement??? Unless the repro ads in the Cormorant were false.

Let's look at it another way. For many years, all exhaust valves have been stainless steel, but when unleaded fuel became the law, the OEMs began induction-hardening their exhaust seats to prevent stainless exhaust valves from micro-welding to the seat, pulling away one molecule at a time and eventually causing recession.

jack vines