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

Empire has had threads on this and AACA forums over the last few years. Here is one started in 2012 so hopefully someone can provide newer information. Perhaps a visit to the consumer website mentioned in the post would have current info.https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=10963&viewmode=flat&order=ASC&type=&mode=0&start=0

A a very fine 54 Pacific probably wouldn't go as high as the mid twenties. You can put a $3100 head on it (if it ever gets delivered), but plan on getting perhaps $500 more on the resale for your trouble.

A 7:1 compression 327 head gives a 7.6 : 1 compression ratio when bolted onto a 359. That is a very livable ratio with a a cast iron head. The larger displacement and moreover the larger intake valves of the 359 will give nice performance. A 8:1 327 head will give you 8.7 on the 359 and will knock so much on the hills that you will end up with less usable performance than if you ran the 7:1 head.

I only recommend hardened seats if you are going to be regularly pulling a heavy trailer.

Thanks, Ross. That was enlightening. My engine has run only an hour in the past 30 years, so one cylinder is not yet firing. But the car runs pretty smoothly to be missing on one cylinder.

My problem with the 327 head has, obviously, been the issue of what compression ratio the car is running. Since I have personally noticed the car running smoothly on 7 cylinders-though smoking like a choo-choo train, I am sure it is not running on TOO MUCH compression ratio right now. I wonder if it would run better on the Edmund knock-off head.

I always add this when talking about valve seats. DON'T PUT HARDENED SEATS IN A PACKARD INLINE BLOCK. It's a high nickel casting more akin to cast steel than cast iron. Adding valve seats helps the machine shop and if they fail will continue to help it. Worried about valve seat erosion? Run Stainless Steel Valves. All told that's a relatively affordable option to seats and they're not going to fail. There's always the occasional splash of race fuel or lead substitutes (which you don't need every time you gas up) to offer the engine a bit of old school protection. The use of Rotella or similar high zinc oil also goes a long way to keeping things protected the old way. Good luck...

Continuing the discussion. I have a '54 Convertible with a 359ci engine. I have been offered a 288 AT head, #420537, casting date 12-17-51. Would this be a suitable replacement for my aluminum Head?

Les

Believe that head is rated 7.5 : 1 on the 288. By my calculation, that will give you 9.2 : 1 compression on the 359 The car will be scarcely drivable without racing fuel.

Thanx, Guess I'll look for a 50-52 327ci standard head.

My 359 c.i.c. engine has a 327 head but I do not know from whence it came-i.e., I don't know the year or comp. ratio of the head. HOW can I tell which head it is?

The casting date will be the best information on the head itself, the casting number isn't particularly useful. Since you don't have a full history on the head the only accurate way to determine the current compression ratio would be to "cc" the combustion chambers and then do the corresponding math.

Thank you for your reply. This engine purrs like a kitty, smooth as can be, so I will just presume it's a 1954 327 head, which gives it almost exactly the same compression ratio as the aluminum head would give me on this engine. The difference, according to the charts on this site, is negligible-which explains why this engine runs so well. All things considered, I am quite confident that the head swap was done back in the day when Packard mechanics were still around in more abundance than today.