Okay - so I dropped a valve on my 440 source heads. So the ProMaxx heads will get a back to back comparison.

I did clean up all the ports and have the springs, retainers and locks swapped for titanium roller cam stuff.

So far I've been impressed everything has fit. The 3/8's pushrods did require substantial clearancing to fit the lowdeck with my mopar 1.6 rockers but everything else has been good.

Sounds nasty in the driveway so we'll see how she runs tomorrow. Hopefully it'll run 5.90's since it went 6.teens with untouched 440 source heads.

Honestly as long it lives the rest of the season I'll be HAPPY!!!