Last week I got back a D7 head done by a machinist I've been working with for over 25 years. The handbook gave me the ability to articulate exactly what I wanted done for my needs. I had left the handbook with sticky notes on certain parts and a list of what I wanted accomplished. I explained to him that I'm a decent mechanic but not a machinist so please check my calculations etc.... When I picked the head up he said the project was actually exciting for him and the Scheyldahl (sp) brothers were right on with their suggestions and calculations.
: D7xx with 302 valve springs, 4.0 valve spring retainers, new backcut Int & Exh valves, hardened seats, head milled .070 and CC's volume tested at 48 cc's , Port divider welded in and Exh flange milled flat, 302 springs have Ford stroker style .060 shouldered spring seats with head milled for all springs 100lbs uniform closed.
As per Falcon six performance compression calculator, on a 200 head will have @ 9.1:1 with Victor 3910 gasket. On a 250 head will have 11:1 with Corteco std gasket.
I am building up the 250 but will put it on a good C8xx 170 block for now which should be 8.8:1 with a Victor or 9.3:1 with a steel shim (I have a few).
It's all for fun- Powerband