heres the problem with comparing two things that arent the same though... You can only compare full out built to the rules versions of the cars... you cant do anything less of that because the rules allow for more...
A m20b27 has an EXTREMMELY narrow powerband, (hell stock rev limiter is at 5800? IIRC...) the e cars, while torquey, are MAXED out at around the number you qouted... However there are examples of m42 motors on the street, with the simple bolt on parts in the 140-150 range... now take a maxed out IT legal motor and you might see a car in the 150-160 range... it IS possible with the right tuning and cha ching $$$$
Only time will tell what needs to happen to the e30 318is however as it is its first year in ITA, being classed in ITS since its IT existance... I would think in its current form it is still very competitive