The 255 was one of the worst ideas of Ford's engineering staff since it had both poor fuel economy and low hp for the displacement. Available only in 1980 and 1981 (mostly in T-Birds and Stangs) it was dropped in late 1981 for the 5.0 (302) engine. Due to some unique parts and its poor reputation, no real speed parts, cams etc. exist. Yes, some 302 W based parts will swap but IMHO I'd skip it unless one is restoring a period correct vehicle.
Car Craft did a article on the 10 worst v-8s back in oct 99. Here is what they think:
Pontiac turbo 301 80-81 Trans-am 210 hp
Chebby 262 75 Monza 110 hp
75-76 Caddy 500 only 190 hp or .38 hp per ci
Olds 350 & 260 diesel 0-60 in 20sec 1/4 22.08@62mph
Caddy 8-6-4 140 hp
Ford 255 80-81 Mustang 115hp 191 tq
Buick 265 120 hp 4 main bearings
Chebby 288 '17 model D 36hp
Chebby 267 79-83 Malibus & Montes 125hp
That's it. 9 GM engines and 1 Ford. They write a good description for each one and why it is on their list. Some of their comments are very funny.