xflow valve info?

I have a bare 250 xflow head I need to complete (but it is 800 miles away)

does anyone know the stock valve size, common oversize for the valves and the stem length?

I have a couple sets of SBC valves and retainers I was looking use.
 
I have measured both the intake and exhaust valve from my stock Crossflow head, here are the specs:

Intake: 1.800" OD, 5.310" Length
Exhaust: 1.500" OD, 4.975" Length
 
The x-flow is a porcupine head, and uses cut down 335/385 valves and, in essence, Chevy Big Block valve gear, with similar hard dimensions to any of those canted valve small, medium and big block Ford engines made from 1969 to 1996 made engines. The Small Block Chev valves won't do it. For years, Ford's Windsor headed variations have used a variation of white box Small Block Chev valves, but the x-flow items are too tall to swap over, even with lash cups.
 
The x-flow is a porcupine head, and uses cut down 335/385 valves and, in essence, Chevy Big Block valve gear, with similar hard dimensions to any of those canted valve small, medium and big block Ford engines made from 1969 to 1996 made engines. The Small Block Chev valves won't do it. For years, Ford's Windsor headed variations have used a variation of white box Small Block Chev valves, but the x-flow items are too tall to swap over, even with lash cups.
 
I bought a set of heads for my chevy and one ended up being cracked. was looking at bare casting or fully assembled heads for the replacement and was looking to maybe carrying over the leftovers to my bare head.
 
I just went through all of this for my X flow head. for my intake, I Found a BBC exhaust valve that was 1.880/5.300 long w/ a 11/32 stem. I had my machine shop turn the valve down to 1.800, otherwise it was the exact same length as the stock valve.
Used a SBC 1.5" exhaust valve that was 4.960 long same as xflow across the board.

Used BBC beehive springs , and they got installed at 1.800,..but I used a spring cup and a shim to get that, as the stock installed height is closer to to 1.900.
Additionally, I used a pushrod guide plate kit from Crane cams that fit the existing pedestal bosses, and the stud has a 5/16 coarse end that screws into the head, and a 7/16 fine thread other end for the rocker. I ended up having my head tapped to 3/8 and used a different stud that I modified as my cam is a solid roller, and I wanted a stronger stud anchor for the rocker.

I used a Comp Cams 1.73 roller rocker for BBF on top of that.
 
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