(just for anyone who was looking for info - like me)
The Q45 MAF maybe bigger but since the Q is a V8 and has 2 MAFS and the air flow readings are limited with the Q sensor because of that. No one likes them (example.. Mckinny motorsports, heavythrottle, phase2motorsport). In fact the Q sensor does not work with late S14 engine, which is what i went though, i was getting a fuel cut at 5500rpm evertime i hit boost, EVEN stock boost! stay away from those Q sensors, bigger isnt ALLWAYS better

. The Z32 sensor is good for 500hp.