cast iron heads vs aluminum for stroked 340

EL5DEMON340 said

How fast were you looking to go? Those Indy X heads are known more as a performance replacement, where your stock rockers and headers will bolt up to, not as a race head, certainly not like a W2. Plenty of guys running 10's and 9's with the IMM preped X heads. What's your combo??

Click to expand...

4.080x3.31
lightened 2032's
11:1 with Indys at 59cc
gear jambing with 3:91's and 27" rubbah

I'm sure there's guys that get those numbers out of their cars but they're 400+ in3 and have tons of time squeaking every lasts bit out of those iron Indy's.....But that can be said for a highly modified OEM casting too cant it?
My issue issue is IMM website and Brian himself claim "270" out of with their "proprietary prepped heads" those numbers are flat out false.
BTW the rocker geometry was out of whack, the GM valves are too short and I had to run lash caps to get roller tip even somewhat respectable.
This opinion is coming from a consumer. I dont build engines, thats not how I make my money. I just like getting what I pay for.
EL5 Demon is on my bucket list, let me know when its time to sell.