Originally Posted by
Marc sierra
You can use the 2.9 sump from the XR4x4, but you have to fit the drain hoses from the cylinder heads to the 4x4 sump.
The BOB engine is a stronger casting and can take slightly more revs, but the BOA engine is easier to install since it runs on the EEC IV instead of the EEC V of the BOB. The EEC V uses PATS (anti-theft system) and needs the automatic gearbox to be present. Although on Fordpower a few people are working on trying to remap the standard EEC V to ditch the autobox and PATS. The BOB engine also has slightly more power because of different cams (which can be fitted to the BOA too) and a different inlet manifold that has a variable lenght.
If you're going for a turbo I'd use the BOB because it's stronger. The ECU doesn't really matter anymore then since you need a remap anyway.
Hi Marc,
Thanks for all that info, especially regarding the block etc, it looks like the BOB will be the way to go for me, especially as I don't intend on using the factory ECU.
Just one question regarding the intake that you might be able to help me with. I'm aware that the BOA and BOB used different inlet manifold mounts but is it possible to use the readily available intakes for the BOA (e.g. Jenvey) with the BOB by using an adaptor plate or similar or will I need a custom lower section to mount the throttle bodies? This is something I can sort out myself but if it's been done before and there's adaptors available it will save me both time and money I'd otherwise use 3D modelling a new lower section and having a 1 off item cast for me. That said I've actually already started the 3D modelling, with information from Jenvey I've got the top half of the lower manifold modelled and only need the dimensions for the head mounts and ports to blend in the lower half, this may still be the best option to minimise any under bonnet clearance issues I can imagine I'll come across.
In regards to the 4x4 conversion, what you've said reinforces some infomation I found a day or 2 ago on another site, link below.
http://www.maddoldbugger.supanet.com