Ford 144-250 inline 6 high performance building
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==Heads== | ==Heads== | ||
| − | When working on the cylinder heads on the older engines (1960-'68) the 1960-'68 heads do not flow well. Replacement 1969-up heads are better, particularly casting numbers D8 and E0 heads, which would come in 1979-'83 model years. These heads have 1.75" intake/1.36" exhaust valve sizes. The exhaust valve seat can be machined to 1.5". The drawback to these heads is the chamber size is 62cc, 1960-'68 heads are 52cc, so compression drops approximately 1 point. There are also Australian cylinder heads with removable intake manifolds, but they are expensive. There | + | When working on the cylinder heads on the older engines (1960-'68) the 1960-'68 heads do not flow well. Replacement 1969-up heads are better, particularly casting numbers D8 and E0 heads, which would come in 1979-'83 model years. These heads have 1.75" intake/1.36" exhaust valve sizes. The exhaust valve seat can be machined to 1.5". The drawback to these heads is the chamber size is 62cc, 1960-'68 heads are 52cc, so compression drops approximately 1 point. There are also Australian cylinder heads with removable intake manifolds, but they are expensive. There was an aftermarket aluminum head developed from the Australian head available from classicinlines.com, but it is not currently available. |
Originally, Ford used a steel shim head gasket that was 0.025" compressed, these are no longer available. What is available today are composite head gaskets that range from 0.045"-0.055" compressed, so the cylinder head must be machined at least 0.025" to make up the difference. If you use the larger 62cc chamber, the head will need to be planed down a bit more depending on the desired compression ratio. These heads can be milled 0.090" maximum. | Originally, Ford used a steel shim head gasket that was 0.025" compressed, these are no longer available. What is available today are composite head gaskets that range from 0.045"-0.055" compressed, so the cylinder head must be machined at least 0.025" to make up the difference. If you use the larger 62cc chamber, the head will need to be planed down a bit more depending on the desired compression ratio. These heads can be milled 0.090" maximum. | ||
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