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

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As a fan of English cars I would not say worst. Although the special pleading and head in the sand attitude of the industry and journalists of the fifties and sixties can be amusing.

I felt bad when the English auto and motorcycle industry finally died, as you would when an old friend died of a disease that could have been prevented or cured had he listened to competent medical advice.

Rusty, sooner or later most owners of 359 engines are forced to replace the aluminum head with a 327 cast iron head. At that point, and I speak from many thousands of miles with such as 54 Packard, premium gasoline will be most appropriate, some would say essential.

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Do you know what the compression ratio would be? And do you mean 92 octane premium unleaded?

I also question the necessity of special oil in a flathead engine.

The reason modern engines do not require zinc is that their OHC valve trains are short, light, and lightly loaded. The old pushrod OHV engines had a heavier valve train and stiffer valve springs and consequently, more pressure on the cam and lifter surfaces.

A flathead has similar light valve train, light springs etc to an OHC.

In fact I believe the use of zinc began in the early fifties after a spate of cam and lifter failures on the then new OHV engines, particularly Studebaker and Chrysler although other makes were not immune. This was something new as the old flatheads had never experienced such cam and lifter failures.

That's so interesting . So Basically the 359 engine can cope easily with unleaded petrol, no conversion needed? And in that case no special engine oil required. Makes life alittle more easy

I would still run whatever oil you prefer and a zinc additive, even every other oil change, because it's cheap insurance. But i too have read that this wasn't a flathead problem, it comes from the higher spring pressures and more aggressive cam profiles of the OHC engine.

Can the higher spring pressure be fixed? Or just something we have to live with?

From what I understand, there is no need for going to a zinc additive unless you have a new camshaft, or a reground one, and/or new or refaced tappets/lifters. Modern oils have enough zinc to provide provide lubrication to these parts. A seasoned engine will tolerate the new formulated oils just fine.

But, having just said this, I use 15W-40 Classic Car Motor Oil in my Packards. This is a motor oil that is formulated for engines of our Packards' age and for those that do not use a catalytic converter. It is sold by a region of the CCCA in case lots. It may be overkill, but it makes me feel good.

(o{I}o)

Edit: I believe, that those with the old style straight-8s with roller cam followers should have no concerns about the new motor oils.

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It's part of the design of the engine. Pushrod engines have a heavy complicated valve mechanism. They need heavy valve springs to control them. This means heavier loads on the moving parts.

Pushrod engines built since the early 90s usually have roller lifters. These eliminate sliding or rubbing at the most heavily loaded parts, and substitute a roller bearing. This eliminates friction and wear at the most critical point.

It is not practical to change a flat tappet engine to roller lifters. It can be done but the expense is not justified.

The engines most in danger of cam and lifter failure are high performance pushrod V8s of they type used in most American performance cars from the early fifties to the early nineties. The more radical the camshaft, the stiffer the valve springs and the more critical proper lubrication becomes.

Flathead engines, overhead cam engines, and engines with roller lifters are not prone to excess wear here.

Gary,

Rebuilt 359 Engine and Trans for sale over on the PAC Site. If yours is seized this could be the easy way to go with everything already done, and looking good too!