It's also worth looking at the different CVH's there are CVH's and CVH's... Ford manufactured multiple variants of parts all badged the same part number for the CVH. Especially around the cylinder-head. They even salted out a batch of rally homologation heads onto production line builds.

You can swap some of the parts from different capacities around.. so if you have the 1600cc CVH Hemi head you can fit 1300cc dome top high compression pistons.

Its worth looking at some of the simple things as overall the CVH engine is limited by valve lift duration and piston top clearance... without turbocharging.

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