is there any diffrence on the heads of an early 2wd cossie (88) and a late 2wd cossie and a 4wd cossie?
cheers aaron

 

4wd and 2wd are different compression ratio, different cams, different externally too where the turbo hanger goes.

not sure about late and early differences.

Sorry, im no expert so cant really give you anymore than that but figured I reply just with at least a vague outline as im not sure what level of detail you need so it might still be useful, im sure someone like north yorks can give it to you chapter and verse though tomorrow

 

cheers chip. im just after general info because people always seem to state that they have a early 2wd head modified so does that mean its a better head or worse head? lol so out of the 2wd heads and 4wd head which one can handle more power.

 

As far as im aware mate, they can both be modified in similar ways, and will both do similar power as standard, ie no significant difference, still the same fundamental port shapes and valve sizes etc

 

cheers chip.

if anyone knows the diff between an early 2ed saph and late one dont be shy

 

The main difference between early late 2wd heads, is 3 door and sapph.
3 door heads have a closer fitting area around the stud/bolt holes, meaning they take a smaller headed bolt or stud nut/washer combo than later sapphy heads(2wd) that have more space around the hole to take a larger stud/nut or bolt, so better clamping force more evenly distributed.
4wd heads have different INTERNAL waterways, between the block and head, 2wd have long slits, 4wd have two round holes so support gasket better, for more power and so are favoured.
Port shape is SLIGHTLY different, but not hugely so, and once ported neither head has an advantage over the other save for the better support of the later 4wd head gasket.
4wd sierra head not quite as good as escy head, but so little in it, escy is slightly better on emissions as a result of burning characteristcs.
tabetha

 

also late 2wd heads have 3 bolt holes for thermostat mounting means you can use a 4x4 thermostat on it early 2wd heads on have 2 bolt holes