455 Exhaust plugs on heads??

[BulletBill]

I have a question for the 455 folks. I tore down a friends 455 today and there wasn't any exhaust plugs for the ports in the heads that allows exhaust to run through the center of the intake from side to side. On my 455 the plugs are there and I left them in because I wasn't sure if I should take them out or not. My question is, what is the purpose of these plugs and is it o.k. to run without them? aviator@arkmola.net

[GlastronGuy]

Are you talking about the plug shown here in the top, center of the picture? If so, you need them with an aluminum intake manifold or you run the risk of cracking it.
http://home.attbi.com/~glastron_carlson/wsb/media/93515/site1031.jpg

[sidewound]

Also you should run them because of performance reasons. Preheating the fuel air mixture isn't needed. It's a hindrance to performance. Cooler mixture= better atomization. When I raced cars in the old days I ran a coil of fuel line through a coffe can of dry ice just to try to cool it in hot weather.
Peace Man
CESAR

[GlastronGuy]

Good point about performance. That tray in the pic also helps keep hot oil off of the manifold keeping it cooler.