the thiteks are a great option and come with a decent port job standard. i run the 2.20 thiteks on my motor and they are fantastic. honestly though, intertias porter can get as much or more than the thiteks on a apache head. might be worth saving yourself a thousand bucks. the thiteks are 3499.00. either way is a great choice. do you already have apache cores?
I've got 6.1 cores. I figure as long as the short turn can take it, the throat can be resized to take advantage of a bigger valves. Not sure how much difference there is in the short turn area between each head.
You'd want to get a set of Apache heads if you want to be comparable or in the same ballpark as the thiteks. The 6.1s fully done will get you maybe 370cfm@6 fully done with a bigger 2.10 valve. The apaches come stock with a 2.14 valve and ported can get 390-400 with bigger valves. I just had my local guy finish up a set of apaches with stock 2.14 valves for me and he got 380cfm@6 out of them. The standard thitek head with a 2.1625 valve flows in the 385 range
Could you not get the throat and valves bigger in the 6.1 cylinder head?
Seems to me if you could get that, then you would be able to attain those numbers. Again, thats assuming the port shape and the amount of material is the same. Also, I'll be going on up to 0.800in valve lift. Thats my plan anyway so I'm hoping the flow curve continues upward after 0.600.
I also just bought a set of titanium valves that I'll have cut down to suit my needs. As is the intake is 2.15, and the exhaust is the same diameter as stock.
