much easier to just fit the 24V engine from a granada or twin turbo the normal 2.9

you are limited to around 6k rpm in the 12V form and about 6500 in the 24V form

the 4.0 won't give you 4.0 as you need to use some other mods to get it all working right, not too sure as it's been a while since it was discussed by someone, as in a good few years ago

if i can dig up the info i will do so, but it's a lot of wor for not a lot more power