455 ID

[shoreice]

How do I identify a 455 at the junkyard? What year is best to run on 93 octane? Thanks,Kenny

[Smartin]

Look for 5 bolts on the valve covers. The 350's had 6 holding them on.

You can run any of them on 93

[shoreice]

Thanks for this answer, it makes my search much easier.

[Guest buickapollo455]

455 had a cast in the valley behind back top of intake "455" and 350 had same "350" , the years 71-74 are cast in the head forward of 1 cyl, with year in 2 digits 71-72-73-74, in head, under the 70 intake under side is cast in bottom of intake 70. All serial numbers are in 1 cyl galley on block till 71 after this it is at oil pump flat on front of the motor, each is started as 4 for buick, and next the year 0-6 for year 70-76. the 3 is a letter significant of plant the motor was made H is flint. the last 6 are the serial number off assembly line or match to car serial last 6. 70 is 10.5 one compression, and 71-74 are 8.5 to one, 75 and 76 are 7.9 to one but the best oil galleys in the factory block. using 71-4 heads are best with late block. dont use 71 or older on late block without aftermarket intake or early intake. heads pre 70 had oiling in shafts and late had oiling thru push rods, better oiling. Buy the book "guide to buick performance" by dove at your favorite book store best buy you ever made. hope helps craig