Indy heads single water crossover /single plane manifold.

How much cam is in it? Just so I understand, all the timing isn't in until 5500?

When I first ran my Indy headed 434 the temperature made wild swings very quickly. Installing a nipple in the intake and a bypass hose cured the problem. I run a 160° high flow thermostat, even in the hottest weather I've never seen it over 185°.

BTW, I run a MP viscous fan with a factory pulley driven by a 5" crank pulley.