How is primary length measured?

[winders]

Originally Posted by rbogh901

Those Mufflers are phase 9 correct? It seems they have become less common. What has superseded them?

How important is the short segment megaphone after the collector?

The mufflers are a clone of the Phase 9 mufflers. A lot of air-cooled race cars here in Northern California use them.

How important? You mean the collector to exit transition? Critical!