Hi Dead,
It is my understading after doing some reasearch, that puller fans are more efficient than pusher fans (up to about 20% more efficient).
Having said that, I think some guys with pusher fans also keep their stock belt driven fans operating....I am not sure what effect this would have on the number above....
As indicated above, since I am going with the puller fan, I am eliminating the stock fan/snout and going with a fan eliminator kit from Rick Patton.
Cheers,
M. Pied Lourd