Mk5 Turbo Di & diff ratio upgrades

[Levi79]

Hi there, I'm new to the forum, I have recently aquired a mk5 transit tourneo, its a 2000 (W) with a 70PS banana in it & a front loading square beam axle with a 4.56 diff.
The engine is fine, but I would like more power, especially as I'm gonna put a taller diff in, 1 - its a bit screamy at motorway speeds 2- the electronic speedo is about 10mph out, which made me think at somepoint it had an axle change, but the chassis plate codes say it has a 4.56 diff in which corresponds with the tag on the axle.
So been doing a bit of research on here & other places, & I understand that a 4.11 & 3.9 diff was also offered, I also understand that these are quite hard to come by! So does anyone have any or know anyone that has any, or can anyone point me in the right direction of solving my dilema with a crown wheel & pinion from a different diff? do the rear loaders have the same crown wheel & pinion that would fit? does my axle share the same with things like older or newer transits? escorts, capris, cortinas?

And also can anyone point me in the direction of a good turbo engine? or even a turbo & manifolds to fit on my current engine?
I'm watching a turbo engine on ebay, but it has the ecu controlled pump, looking at it, looks like I could swap it for the bosch pump on my Di? is it that straight forward or does it need other mods?

Also after a set of standard steel wheels for it, unless I can get a set of mk1-2 ones with the chrome hubcaps?! (don't ask, I have a thing for retro chrome hubcaps on newer vehicles!)
I've been in the motor trade for years so with any of my queries I'm not adverse to a bit of fabricating/welding/stripping & rebuilding/making a good one out of two to get the desired outcome!
Many thanks for any responses!
Levi

[Altransit]

Welcome

You can just turbocharge the engine that you have It's been done by a few people on here

[MinorMatt]

3.9 was only available up to 1991. The whole diff won't fit, but you can swap the mk5 diff center in to a mk3 diff.

Rear loader cw&p are very different

[Levi79]

Thanks guys, so are there any crown wheel & pinions from other ford products that will fit? or even other makes? just trying to widen the variables of the search! I've seen a few banana turbo conversions, I'd rather just change the whole engine as I'd have to either locate or fabricate manifolds, oil feeds & returns, find a turbo, a whole engine will have everything I need, plus the correct injectors etc, plus I can off set some of the cost by selling the Di lump, like I say the turbo engine with the lucas epic on it looks like a viable option, it comes with the gearbox too! I can just swap my mechanical bosch pump to it, could be a project over the xmas holiday! I think the diff is gonna take a lot longer to source

[MinorMatt]

Your stuck with transit diffs... sorry

[V184]

taller tyres ?

[vanfox]

......or overdrive....