Smallblock intake manifold shootout.

The older designs are just that. Old. The LD340 is a decent part, but it's an aluminum version of the '71 Thermoquad intake. A good part, but limited for top end power, and heavy as heck. The RPM is taller, and not factory looking, but it goes a LONG way to be better than anything previously released for a street or street/strip performance engine. They did thier homework and it shows. It's good enough to feed 4" arm engines too. That's saying a lot. The small block SD was an ok manifold for it's day. That day's past. Conversely, for a B wedge, it's one of the best all around intakes you can get. Everything is different. The Victor is designed for larger inch engines and is sized for them. Making it soggy for street stuff with 3.31 stroke. The 6bbl is a dual plane, but it is very restrictive. In fact, the 6bbl setup was 35hp lower than an RPM and 950 Holley on a 416 I built when dyno'd.