Cat,

I did allot of number crunching the total surface aria of the stock head is 35,538.22 mm2 and the NOVA head is 46,437.00 mm2. The NOVA head is about 31% bigger, you’d think that more surface aria equals more cooling. Not the case here, the K factor of the 6061 (stock) Al is 104, and the K factor on the 7075 (NOVA) is 70. The stock head is anodized witch reduces its efficiency at cooling the engine. My best calculations say that the heads cool about the same, one is no better than the other. So unless you’re going to get it for the look or the strength factor like I did, I would say stay with what you have. If my testing shows different results I will post them.

Stock head weighs 71.56g with 11 cooling fins
Nova head weighs 82.81g with 15 cooling fins

Diff cup
Stock plastic = 3.50g
Nova Al = 8.90g

I hope this helps, like I said I will post actual results once I get the truck on the road and get it tuned.


Bryan