1973 Pontiac Firebird Formula 455-SD

[Stan Weiss]

Originally Posted by Travis Miller

Refactoring of engine horsepower by NHRA actually started as early as the 60's but it was kept a secret for whatever reason until they published a book called the "Factor Finder" in 1972 followed by an updated version in 1973. Sometime in 1973 is also when NHRA started listing the refactored horsepowers at the bottom of the column in the classguide.

What engine combo are you trying to find out the date when it was refactored?

Stan

[oldskool]

There is bound to be somebody here who either has or knows someone who has a copy of one or both these "Factor Finder" publications.

Once again, do you have one or both ?

Do you know anyone who has one or both ?

Does anybody know of an online copy of either year, hopefully a pdf or some version that can be viewed and/or copied or downloaded ?

Gotta be a copy, somewhere. Somebody PLEASE help me locate these "Factor Finder" publications !