[Jim Brierley]

I've never thought #4 ran any hotter, but have never measured it. I do run electric 'pusher' water pumps, this may help. I've thought of doing similar to what Ed in Maine talked about, only using an internal water manifold like Chrysler products used, aiming water at the area between the ports, where cracks often appear. I would only do this on a race engine, too much useless trouble for street use.