Yep, keep all the heavy things inside the wheelbase. Polar inertia is the key...
I have also run with the engine in the front, (A12) and then with a 13 inch setback (this was the days before they limited the setback to 300mm) and it made NO DIFFERENCE to lap times, it was no quicker off the line... geeez I was pissed off...
I think the A motors are just so light, and the chassis is pretty much bangon that makes it a less rewarding modification than say shifting the pinto rearwards in yer Escort!..
The only difference I could detect (and I couldnt prove it) was an increase in top speed at Pukekohe. I think this was due to better airflow thru the front end and out again..
I ended up putting the radiator back up the front after the engine setback, I ran for a while with it as in the piccy above, but it was an aerodynamic disaster area.
The combo that worked beautifully was with the radiator up the front, ducted out thru the inner guards and a flat undertray from the crossmember as far forward as they will let you get away with
- the undertray has to be strong enough to stand on, I'm not joking!!
Anything heavier than an A series motor would make a setback mandatory I reckon...
The 240RS is an utter dog with 180kg of FJ20 up the front....