86 Capri Cylinder Head Selection

Guys,

I've got an older 351W crate motor (M-6007-B351) with cast iron GT40 heads. This is a mostly street car, but I'm looking for a project to get into and I know that there are many heads out there that are better then the old GT40's. I was going to switch over to a roller cam at the same time and was realistically hopping for a 75 horsepower increase between the two updates. Here is my issue, I'd like to stay with the stock hyperutectic prisons that were a 9.1 CR. I'd want to go with a smaller 58cc chamber to raise my compression a bit. The problem is it seems like every head I'm interested in has 2.02 valves. On some articles I've read that the TFS Twisted wedge will work with stock pistons but on other sites or even the summit catalogue, TFS want you to use unique pistons in conjunction with those heads. Inexpensive heads from Pro Max, SVE/LMR, Edelbrock E205's, and NKB are all 2.02's.
I don't really live at the strip anymore, but to be honest I just finished building a LS based LQ4 6.0 liter for my wife's 2000 corvette and even though I purposely built it on the detuned side for her it seems quicker then my car! I feel like a smaller valve, 170 head will be too small to bother with on a 351. Any suggestions?
 
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A twisted valve head has nothing to do with this. The fact that TFS twists the valve, and makes for a potential interference when using it makes that head a non-contender. but what about AFR, or Edelbrock, or Any number of 2.02 valve inline heads that make up 99% of your other options out there, as opposed to the too small 170's your considering.

What's the issue?
 
My issue is I don't want to flycut pistons. I get that a 170 is small, but so is what I have on now. Thats why I'm asking about a head selection. Some older articles make mention of the fact that the TW head was able to clear stock pistons with the larger valves, others directly dispute that. unless, I'm mistaken it Seems any 2.02 head would require flycutting (conditional to cam specs). Does anyone make anything like a 205 head with 1.90 valves that wouldn't create piston to valve clearance issues.