the technical reason to put it close as possible to the throttle body is that the "column" of air inside the pipe distance between the bov and tb will be minimized, making that air that hits the tb plate and 'turn around' smaller, and thus less lag....but the difference is really un noticable and its not really able to be proven, esp wont matter on a street car.

i prefer hotpipe, simply because it makes recirculating alot easier and no giant recirc hose stretching across the engine bay (mine is like this, and im going to fix it).

recirculating a bov on a pull-through mafs style car will do the following:

1. better mpg. yes, true.
2. quieter. less ricers, cops, and thieves to hassle you. bovs are not bought for the sound.
3. no gay richness between shifts. this is the reason for the better mpg, as well as less black burn marks on your rear bumper (if you have an N1 angled style exhaust system), from excessive richness. less popping, stuttering, and general crap that 99% of SR owners have that just peeves me.
4. NO STALLING!


my ka-t get ~250-260 miles to a tank of gas w/open bov or check valved (to cause it to not open at all and just surge). not only does it make the iacv work harder and the car wants to stall all the time. hooked up my recirc tube again (it was off because work clamps suck), instant difference. car gets 300+ miles to tank of gas again (both tanks were easy daily driving, occasional hard boosting).


just make sure the BOV has a direct vacuum line to a port on the intake manfiold. i think in terms of functionality and cleanliness. while putting it on the hotpipe makes my recirc tube short and clean, ill run a longer vac line, as opposed to vice versa with it on the cold pipe. being i can bundle the vac line with the harness, ill take that option.