I know 100 percent you have to change the seats to put a valve larger than 2.10 in the eagle heads.
Alex p.......that whole ultra high velocity, low flowing early 5.7 head was cobbled up by Craig at gtp. It has been proven wrong for years. If that were the case, the 6.4 Apache head would be a lot smaller. They went exactly the opposite direction for a reason. I'll trade velocity any day of the week for a properly designed larger csa head that flows 60cfm more. Take your "max ported early 5.7 head and throw it on a 426, then swap out for a set of thiteks with 2.20 vales and MUCH lower velocity numbers and the motor will make 70-80hp more with the thiteks

High velocity works. Don't know who you are, what your relationship is with Craig or if you have any more experience than vendor shopping people for information and comparing notes but I'm happy with my small port Eagles. I'd be happy with a worked up set of early 5.7 heads too. No reason for me to own a thitek, ever.

I put my money on that gamble and I know what my expectations are.

I was working on and porting 5.7 and 6.1 heads before even gremlin Steve Alex. Steveo is a bright dude and a helluva guy. But The thought that a motor won't benefit from a larger better flowing port with a larger csa is silly. I only speak of what i personally know to be true from experience.

next thing I want to try and big Thanks to Dustin for sending some banged up heads, is stuffing the 03-08 5.7 head with a 6.1 valve. I really think the original 5.7 heads can be an awesome high velocity head which I would think 320cfm around .6 is easily possible because I hit 312 opening the throat probably a little to far

I know 100 percent you have to change the seats to put a valve larger than 2.10 in the eagle heads.
Alex p.......that whole ultra high velocity, low flowing early 5.7 head was cobbled up by Craig at gtp. It has been proven wrong for years. If that were the case, the 6.4 Apache head would be a lot smaller. They went exactly the opposite direction for a reason. I'll trade velocity any day of the week for a properly designed larger csa head that flows 60cfm more. Take your "max ported early 5.7 head and throw it on a 426, then swap out for a set of thiteks with 2.20 vales and MUCH lower velocity numbers and the motor will make 70-80hp more with the thiteks

Lol.....I actually would if I had a set of each not in use ......on my 423 a set of thiteks was worth 40 horsepower at the wheels over ported 6.1s with stock valves. The thiteks had 2.20s. I still love your duster.....One of these I will get to see that beast

That's impressive! The next time I blow a motor I'll be looking for a different set of heads.

What part of Texas are you in? Austin? We'll have to meet up and talk cars.