Late Escort Cosworth EECIV Small Turbo Head
Posted: Sun Sep 21, 2008 8:39 pmPhil,
To my knowledge everything from the V89HF casting on has the closed in exhaust side water jackets. So Sapphier on I think. This version on also has the more hemispherical combustion chamber with slightly smaller CC volume. Only the V86HF part number casting got the open water jackets.
The YBP V93HF casting has ~1mm thicker webbing in the spark plug valley compared to V89HF at least. Probably to make up for the reduced lateral stiffness of the YBP rocker cover.
The YBP has a water gallery between the inlet ports not present on at least the V89HF. This could limit too much is just right port jobs.
There are some small difference in the lifter chambers as a result of coil pack mounts and different stud pattern of the rocker cover. Not significant though.
The YBP rocker cover design does not lend itself to distributor and spark plug leads.
From previous discussion with Danny the new head he has is a V92HF YBT casting for a large turbo Escort Cosworth.