Quote:
Gary Marshall wrote:
Can the higher spring pressure be fixed? Or just something we have to live with?
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.
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