core attitude:
I know that big blocks win the war but how come all those white water racers run built small blocks? Is it due to the overall weight of the boat or some type of class restriction? Some of those boats get up and go and I've always liked the sound of a small block at high rpm.
PeteWhitewater boats like to be light. There are plenty of big blocks and the 4 time world champ has a 600ci BB ford. Unlimited is anything you can afford to run (blowers, turbos, over 470ci ect); "A" class is up to 470ci; "B" class is up to 366ci; "C" class is generaly up to 360ci. It is up to the individual on what he wants to run. The small blocks are build very strong and spin 5800 to 6800 rpm for 500 mile in a marathon race. The big blocks don't need to run that rpm so they tend to be a bit more reliable. Check out the Eagle tunnel thread; that boat is running a 454ci small block (650HP) and pulls 105 to 107 at 3600'altitude.