Distributor recurve

I don't recommend manifold vacuum on a street car. If for no other reason, consider this. If the vacuum can goes out, the car's gonna run like **** until you can get to some tools and either replace it or bump the timing up until you can get it replaced. With it hooked to ported vacuum if the vacuum can goes out, you can at least still drive the car almost like nothing's wrong. There are a few more benefits to ported vacuum, but that alone should be enough.