This is a pair of Don Losito Ultra-Pro Ford SC1 heads that have been CNC lightened & fully ported with Titanium 2.180" x 5/16" intake & 11/32" x 1.600" exhaust valves from Xceldyne, and they have Xceldyne ultra-light steel retainers (much more stable that titanium at same weight) with titanium locks & Isky Tool Room springs.
A ported 2932 Edelbrock/RYR intake is included and so are the A1 12-point head studs (for Dart block) plus T&D shaft rockers with solid bars and 1.7 intake, 1.65 exhaust ratios with special tapered 7/16" pushrods. The heads have some nice CNC milling work done to them and non-offset lifters were used with those pushrods on a 9.200" deck block.
These were just pulled off a 390 CID World of Outlaws Late Model engine built by Pro-Power Racing Engines in WI. The engine was purchased from Darren Miller, and he claimed the engine was freshened with new parts 300 laps ago by Pro Power & he claimed Pro Power made 830 HP and 630 TQ with it. The engine was not raced after it was bought from Darren due to a class rule change that only allowed a Spec Brodix head.
Losito makes some very nice heads, have used servel over the years. As far as nitrous head, if the champer has a good layed back shape I would say yes, if not they need a little work in the champers. Also look at the springs, for what is used on roundie engines isn't alway good for straight line racing.