Packard V-8 CID race What if?

Posted by Craig Hendrickson On 2011/2/10 17:44:24

There was a displacement and horsepower racing going on in the 1950s and 1960s. Packard was in the thick of it, primarily against Cadillac, its perceived rival, but Chrysler with its Imperial and 300 series and Ford's Lincoln were not far behind.

What if Packard had stayed in business with enough resource to continue its participation in this race? Cadillac certainly did continue, culminating in a 500CID engine in 1970. Here's a table comparing Packard and Cadillac. The Caddy displacements are real and the post 1956 Packard displacements are "What if?"

<table><tr><td><b>Year</b></td><td><b>Packard</b></td><td><b>Cadillac</b></td></tr>
<tr><td>1955</td><td>352</td><td>331</td></tr>
<tr><td>1956</td><td>374</td><td>365</td></tr>
<tr><td>1959</td><td>414?</td><td>390</td></tr>
<tr><td>1964</td><td>440?</td><td>429</td></tr>
<tr><td>1968</td><td>500?</td><td>472</td></tr>
<tr><td>1970</td><td>-</td><td>500</td></tr></table>

The 1959 Packard 414CID I took from this article:http://www.1956packardpanther.com/PV8C/HRM195702A.html

This displacement could have easily happened in 1957. We know that this stroke (3/8in over stock 1956 3.500in) actually worked in the 1956 352 block. BTW, the bore was the same as 374 (352+0.125).

The 1964 Packard 440CID I took from reports that Black Bess prototype had an engine of that displacement. It is just the 414CID above bored another 1/8in, so that would have also worked in basically a 1956 374 block if the bore walls were cast equivalently thicker. This displacement could have also happened in 1957, but Packard may have held back for whatever reason.

The 1968 Packard 500CID I took from reports that this was the "ultimate design displacement of the Packard block." Given it's large size (5.000in bore ctr-ctr) and tall deck height, this is certainly reasonable. One configuration would be 4.375in bore and 4.165in stroke. The bore would be +0.125 compared to the 440CID with a larger stroke of 4.165in. This stroke would have required modifying the lower block casting significantly. Also, other bore/stroke combos are feasible.

Other related "What if?" like cylinder heads, cams, etc could be discussed if anyone is interested.

Craig