Griff is spot on, you need to slow the water down a little so it has time to cool the passages.

I am not trying to start a fight here but slowing the flow to improve cooling is a common misconception. Slowing the flow will raise the temp of the coolant more as it leaves the block but that is different than the amount of heat the coolant actually removes from the engine. Also a higher flow rate has a better chance of eliminating steam pockets by scrubbing the steam out as if forms.

The greater the difference in temp between the coolant and the block the more BTU's are removed.

Having said that restricting the outlet can result in higher water pressure in the block which will raise the boiling point. I think more flow is better.

Bam - I am in pompano as well - need to measure if those puppies will work on not and today is Ma day ...get back to you soon.

Mark, I've known you since the Everglades Marine poker runs starting in the '80's and respect your opinion. (I was alternately on Jenny's Express or Lethal Weapon, you of course ran the classic red BAM) This is one of those issues like, 'Do you run a crossover pipe or a recirculating water pump.' Either way will work, we've just found the best success with restrictor plates, Being tomorrow is Mothers Day It's like competing about who's Mom makes the best apple pie. Cheers Mark.