Seperate the motor and the going rates on CP/PY/Hemmings and Ebay breaks down like this.
Heads worth $14-1800 (maybe more if rebuilt)
Block, HO 455 rebuilt ($23-3000) Block/crank/rods alone unmachined probably $12-1600
HO exhaust $4-600 Carb is a bonus.
I have the 7F6 HO heads and a 71 and 72 HO intakes. I needed the 71 block/heads/exhaust for the 71 intake I have. But I seriously believe the seller will not let it go for any less than $5000-6000 (comparable Butler motor).
One can never recoup all machining costs on a rebuilt motor, even if never fired..Unless the builder is Butler/Nunzi/Kauffman/Keiffer. Other than those Pontiac builders, the machining costs you are buying with this motor is a crap shoot.
Assembled, as she sits without the intake (ditch it anyhow, a 455 HO motor without an HO intake looks horrible IMO) I say $4500-5000 and he will have to eat half of the machining and labor. I would pay for all the parts, half of the labor and $45-5000 for this assembly.
The reason HO heads do not sell as much as RA IV (comparable heads) is the huge 111 cc chambers which yeilds only 8.1 to 8.5 to 1 on a 455. If I were to buy that motor, I would put an 871 BDS blower on top with those heads..at 8.5 to 1, that would be a killer motor!
The problem with this motor is the overall cost versus HP. You could build a 455 with 6X heads and have the same or more HP than the 335 advertised for 71 HO without having to decrease the value of the HO motor by milling the heads and intake to raise the compression. Say you buy it, and decide to not use, you could always recoup your money if you do not modify the heads in any way. If you were looking for an HO motor for an HO car you owned, I would pay the money, but for someone looking for a motor just cause, address the fact that there is no intake, valve covers, dist, accessories, fuel pump wires, throttle linkage..and that adds another $8-1000 on top of this. Add another $4-500 for the correct HO intake if desired. With that, for a low compression 455 that is "mild" that is alot of money for little HP.
Kauffman builds 455 combos with intake/carb/dist/valve covers for $6500-7000 and dyno proven.
Butlers 455 combos have 200-250 HP more than this HO motor can provide and are $3000 more.
Fair price to someone who really wanted this for a 72 HO car? More than someone who wanted a 455 for a non-specific application. I would be willing to pay $4500 for the shortblock/heads/exhaust and carb, if the heads have been redone, maybe another $500
Si Vis Pacem Parabellum
1967 Starlight black PMD Engineering 400 Auto 1968 Alpine Blue 400 4 speed 1968 Verdoro Green 400 HO 4 speed 2013 1LE 2SS/RS Inferno Orange Camaro.
