The V8 Owners Forum -

i had a 4.6 built up engine that was set up with carb and dizzy v belt set uo but it's now knackered due to bad storage i have a option to buy a short engine to replace my damaged 4.6 it's a 4.2 that would have been fitted to a rangerover
brand new still in it's green plastic
question is will the head and camshaft etc from the 4.6 fit this engine what are the differences between the two
it would appear to have the same bore

landkeeper wrote:i had a 4.6 built up engine that was set up with carb and dizzy v belt set uo but it's now knackered due to bad storage i have a option to buy a short engine to replace my damaged 4.6 it's a 4.2 that would have been fitted to a rangerover
brand new still in it's green plastic
question is will the head and camshaft etc from the 4.6 fit this engine what are the differences between the two
it would appear to have the same bore

4.2 engine is based on the smaller main bearing 3.9 block with a 77mm. stroke.

You can use the later heads either with the composite gaskets or use tins for a useful increase in comp ratio, the standard 4.2 is only 8.94/1

I think you can use the 4.6 cam but have no idea if this would work well.

You can use the front cover from the 4.6 with the better oil pump but the nose of the crank will need machining for the longer woodruf key to drive the oil pump.

Is your 4.6 block completely knackered? If it's just a couple of rusty bores you could have new liners fitted which must be a cheaper and better option if the block is otherwise sound, and not cracked behind the liners which would be easy to have checked whilst it's stripped.

Kevin.

Kevin