I've been using a GM one, IIRC off a Firebird/Camaro; pulls 5" even though we took no special pains to seal up the crankcase as far as the front crank seal. It hasn't been a problem as far as amp draw, but I run an alternator. I ran a relay for it. It definitely helped the low-tension ring seal on my 368" SB. The whole thing including the catch tank might weigh a few lbs.