San Jose Gear Jammers

In my ignorance about the engine pics.. What the heck is it? There are 8 spark plugs, but looks like only 6 exhaust ports??

Wikipedia said
"Valves for each bank were mounted inside the triangular area formed by the 'Vee' of cylinders. The intake manifold fed both banks from inside the 'Vee' but the exhaust had to pass between the cylinders to reach the outboard exhaust manifolds."

Interesting design idea, I never knew that until now either!