So I posted up in my other thread "old gas" that I may potentially have a blown head gasket. I'll be doing a leak down/compression test in the near future to get a better idea. I currently run MMR Stage 3 PI heads with a custom grind blower cam (pretty small for my setup, .220/.230, 533/571) but that was the largest I could go because I never got my 18cc Manley pistons flycut. If this is in fact a head gasket, I think it would be a perfect opportunity to upgrade to some nicer heads and larger cams. I've been doing a bunch of research on TFS heads, but there really isn't many newer posts or threads anywhere. Mostly from '10 - '12. There are obviously different options/variations to go with these heads (38/44cc, 90/125/150lb springs, etc). I think I've narrowed it down to the 44cc and 150 lb springs. These are what I'm looking at: http://www.summitracing.com/parts/tfs-51910006-m44 Just a few questions: Has anybody seen any higher hp boosted/nitrous setups running these heads with success? I'm not finding many boosted guys on any forums with much feedback. How are the valves in these things? Are people having good luck with the valves that come assembled in these heads? L&M Race Engines put out an article not too long ago about guys running PI ground cams in these heads, and they weren't getting power gains as expected due to the angle of the valve, and they offer custom TFS specific grinds for these heads...any truth to this? Any newer info on these heads since the first year or two since they came out would be appreciated. Thanks in advance.