Now the entries are closed I think it should be safe to post the engines now 
Well here is my engine I used for my car:
Bear in mind that with the cooling of my car the MTBF rises to about 21700km.
I’m curious what solutions you guys came up with for your cars.
the Mono Razor was fitted with an underpowered 3.0 V8, which is really a placeholder.
However, I will say this, the 2.1 Straight-Four, project “Super Four” I’ve developed for future rounds is powerful enough that in initial testing with no other modifications to the existing car, it took 10 seconds off the time set by the car Mono is using in the Shakedown round of the BRC.
This is my Group B engine, pretty similar to yours, Dragawn:
abload.de/img/brc_bayerbmisuv.png
I chose single throttle MPFI to save some Man Hours which I then could put into higher quality parts. Another engine I considered to use was a 652 hp (486 kW) V8 Turbo, but that would have been totally undriveable.
I had the same problem with my V8. I just couldn’t get the power band wide enough so I settled for 450bhp and tried to make up for that with better aerodynamics.
Another I-6 turbo. Although the power band is fairly wide, I should have let it rev higher to widen it further and needed to flatten the torque curve a little more.