[BRENT in 10-uh-C]

Tom, there is an improvement as far as longevity of the engine is concerned (-due to lower RPMs at the same speed) however to fully answer your question giving Pros & Cons, the present condition of your engine factors in greatly. Most Model-A engines that I see are producing well below the rated 40 horsepower that Ford originally designed their engines to produce. Pete is pretty accurate in that a new Model-A was capable of being operated at 60+ mph for long periods. Most Model-A engines today that have a worn camshaft, or poorly sealing valves, leaking compression, etc. are barely capable of maintaining 45 mph, -much less 55-60 mph. If this somewhat describes your Model-A engine, then a 3.54 ring & pinion is not something you are going to be happy with. Even some of the so-called camshafts in 'Touring Engines' struggle due to the reground camshaft profile. On the other hand, a correctly rebuilt Model-A engine with either a new Stipe or Burtz camshaft, along with modern valves and one-piece guides will be a game changer and your Tudor will capably pull those W Virginia hills.

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