[LMSRACER]

Originally Posted by jm455ho

Debating with myself whether to do the middle hole on my High Ports. Strictly race, 12:1 compression, and around 750 HP. Not sure the benefits merit the extra complexity of fittings and hose at that level. I am presently set up to pull water from front and back holes only. Engine is not assembled yet, so now would be the time if I decide to do it.

Assuming that you're running a stock block, stock deck arrangement here's my opinion. Do It.....

Here's why I feel that way. Every pontiac engine that I've ever built and raced always showed signs of excessive heat between the center two cylinders. Some more than others. I feel that by offering the coolant a path out of the cylinder head in the center promotes alot of additional coolant flow from the engine block, through the deck, around the center two exhaust ports and out through the fittings.

Otherwise the coolant is pumped into the engine block, then around the cylinders, through the deck at the path of least resistance and out through the water crossover manifold or a combination of the water crossover manifold and the two hoses running from the rear outlets.

Without the center two hoses who's to say that the coolant flows readily around the center two exhaust ports where the greatest heat is generated.

I don't think that you need to run large lines fron the center of the heads. You could just run some -6 lines from the center to ensure that coolant flows readily in that area.

I also believe in drilling the additional coolant hole in the deck surface of the engine block and the cylinder head just above the lower head bolt/stud between the center two exhaust ports. Once again, as stated earlier, I don't know if that hole can be drilled in a KRE High Port Head.

Just My

Larry S.