Hi guys,

I've had an EF II XR6 sitting in the garage for many years now collecting dust. The original motor has had it and I've been thinking about upgrading the engine and the AU seems like the most reasonable choice.

I've been in touch with Bullet Performance Racing and they are interested in dropping in a brand new AU Series III motor and taking the complete turbo setup from a BA XR6T. They're confident they can get the turbo setup, intercooler, exhaust manifold and possibly the transmission to run nicely on the AU motor. For the ECU and looms they're going to mod (or base it off) the BA because it'll run the setup a lot better than a E-series or AU computer would.

I'm wondering if anyone has attempted a hybrid setup like this?
Is it possible to use the BA transmission?
What's the best brake upgrade for the EF? (I've heard the EL GT brake package is a decent improvement)

Any advice would be appreciated, cheers!

Why are you going the AU engine? any reason in particular?

I'd go with the BA engine, (that would require knotching the K frame for a drop in fit IIRC) Au engine you could get away with modding the sump to fit.

Fitting the turbo manifold off the BA to a AU engine isnt going to work as the ports are oval in the BA and Round in the AU engine. and quiet possibly the studs also wont line up.


BA trans will bolt up to the AU engine no problems, only problem i see (you have got around by using the BA ecu and looms) is the BA trans was wired different to the AU one.

The main reason for this is that if there are any unforeseen issues with the engine during the process, the AU engine is far less of a risk financially. If the BA had any faults, it would be very costly to replace with a second engine as there are never any guarantees with second hand engines.


Would modding the K frame make it harder/impossible to get an engineering certificate? This car will need to pass engineering, so that's another factor that lead to the choice of using the AU engine, as like you said, only the sump needs to be modified for it to fit.

Fair enough on the AU engine cost side of things.

With modding the K frame, its not impossible to get a certificate you would have to speak to the relative governing bodies to do with that in your state, and what and how they require it to be done.

Plenty of BA engine conversions have been done into E series and have met engineering. Pretty sure theres quiet a few threads in here on it being done.