[Flathead Fever]

The best reason to relieve the block is for when you driving down the road with your flathead singing the Little Deuce Coupe song, "Ported and Relieved and its Stroked and Bored". Its not going to sound as good if your only singing, "Ported and its Stroked and Bored" The words FLOW better when its relieved.

59L blocks which are suppose be truck engines were relieved. I've heard all kinds of theory's on why they did this. To prevent the blocks from cracking is one. That does not make any since, why would you remove metal to prevent it from cracking? Better flow for more power in the trucks. If it made more power why would you not do it to all the flathead blocks? That does not make since to me either. I have never read this anywhere, its my own personal theory. The "L" in 59L could have been for "low compression"? Maybe the trucks need a lower compression ratio to prevent detonation under heavy loads. That makes the most since to me.

I bought a 59L to get a factory relieved block. Removed the heads and it was not relieved. Just my luck.

I'm not sure relieving a block on a street engine helps. You probably loose more power from the compression you loose than the benefit of increased air flow. I talked with Tony Baron about it and he said they ran all kinds of flow bench tests. He said if you are going to relieve the block just taper the relief from the valve up to the top of the cylinder rather than relieving the whole area out. That's what I have decided to do with my engine project.

One consideration rather to relieve a block or not will be the heads you use. Originally some of the manufacturers made two different style heads. A "race" head" which is thicker, requires longer studs and the compression ratio was calculated assuming you were relieving the block. Then there was the "street head". It could use the original studs, and was not as thick as the "race heads". It was designed to be used on a stock block that was not relieved.

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