Packard Forum Index » Modification Discussion

packard1984 Quote:

In 1957 Pontiac's V-8 was 347CID and in 1958 it was 370CID, obviously very close to Packard's 352CID and 374CID of 1955/1956. The heads were also very similar.

Pontiac's performance camshaft of that era was the Isky E-2 which was a mechanical flat tappet design with the following specs:

Int/Exh duration: 270deg (IVO 27BTDC, IVC 63ABDC, EVO 59BBDC, EVC 31ATDC)) advertised; 210deg at 0.050in tappet lift, gross valve lift 0.424In minus 0.020In valve lash (0.0404In net), 108deg ICL, 104deg ECL with 106deg lobe separation.

Packard's rocker arm ratio is 1.6:1, greater than Pontiac's 1.5:1, so the gross/net valve lift on a Packard would have been 0.453In/0.431In instead.

This was a pretty mild camshaft by today's standards, but was a "hot one" back in the day. I believe that one could get one of these cams and the requisite adjustable pushrods for a Packard V-8 from Isky back then too.

Craig

Quote:

For experiencing ultimate valve adjustment agony, one should try setting the valves on a '56 Studebaker Golden Hawk equipped with adjustable pushrods.

The pushrods require three hands to hold the wrenches (pushrod body, adjuster nut, lock nut) and a fourth hand to hold the feeler gauge. Problem is, on the rear four cylinders, there's not room for two people to work under the corner of the low Stude Hawk hood.

FWIW, I've got a couple of the Isky cam, lifter, pushrod and valve spring kits for the Packard V8. Few are man enough to run them these days.

jack vines

"FWIW, I've got a couple of the Isky cam, lifter, pushrod and valve spring kits for the Packard V8. Few are man enough to run them these days.

jack vines"

Well now I hafta have a set. :) PM sent

In the 1979 Iskenderian catalog, the complete kit; cam, lifters, springs, pushrods and retainers, was $446. In constant dollars, that equates to $1,463.63 today.

However, that cost assumes anyone/everyone could buy as many as wanted at the catalog price. Trying to value the maybe only remaining Packard V8 kit is difficult.

jack vines

To get an adjustable valve train you may want to look at a modern shaft mounted rocker kit, possibly a small block Mopar or FE ford. If the detentions look close one may be able to trim this adjust that to make it work. You would have catalog replacement parts, slightly less friction in the engine so more power, and possibly more rocker arm ratio translating into more valve lift, plus the adjustability you are looking for.

Quote:

The 'detentions' aren't close. If it were that easy, we'd have done it fifty years ago instead of the hassle of adjustable pushrods. The two engines you mention, shaft diameters, rocker lengths, pushrod ends and cam/valve angles are all different. The Ford FE is closest, but still a major hassle to make work on the Packard. BTDTNA.

At great difficulty and expense, I did convert the Ford Super Duty big truck 540" engine adjustable rockers to fit the Packard V8. It requires custom shaft bushings, custom rocker stands and a custom taller rocker cover. That, plus the SD rockers are NLA.

jack vines