I have an Engle 238 duration 540 lift single pattern on a 110 in my 468 now. It sounds great, pulls good, but has very little vacuum. #390 heads, ported, with small valves, old Wieand dual plane, nice worked Q-jet, TRW flattops, behind an automatic in a 75 Camaro. This car has to be streetable, and get decent mileage. I'd hate to put one in too small, but it has to go 50 miles round trip to the cruise spot (Winnipeg). Maybe a 3:42 gear out back would be a nice compromise, unless I keep the 4:56's and go an overdrive tranny. Your thoughts, gentlemen.