View Single Post
Old 03-02-2015, 08:26 PM   #1
Travis Miller
Member
 
Travis Miller's Avatar
 
Join Date: Jun 2007
Posts: 478
Likes: 1
Liked 276 Times in 27 Posts
Default Re: Hp refactoring dates

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?
Travis Miller is offline   Reply With Quote