that is true for almost anything that is boosted. im not saying it a waste of time to boost one of these motors, im just saying its a waste of time to twist it hard. ive put some of the most retarded gaint cams ive ever used in this motor.
i really dont see how you can even compair the two, the b series have way bigger heads, the ABA has a 92mm stroke vs the b16 77mm so right off the bat you have 1000fpm more piston speed at 8000 (500fpm more for the b18), then you have to try and blow all that throu a single valve head that dosent really flow all that great to begin with. looking at the numbers alone this thing has as much piston speed at 8000 as a b16 turning 10000.
im not saying its imposible to make power with this motor, ive done it before, im just saying the odds are not in anybodys favor if your going for more rpm. 20 pounds of boost that gos nowhere at 6000rpm wont go anywhere at 8000rpm either and a cam wont help much unless its big, like $1500-$2000 big, by the time you buy all the lifters, springs, and other bullshit, and do the machine work to make it all fit. this is why i dont fuck with vws anymore, they are all shitty motors to try to make fast.