Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - mpg question
Thread: mpg question
View Single Post
  #8 (permalink)  
Old 04-03-2013, 09:24 AM
oldbogie oldbogie is offline
Registered User
Last photo:
Join Date: Apr 2007
Location: Seattle, Wa
Posts: 8,885
Wiki Edits: 0

Thanks: 10
Thanked 1,068 Times in 885 Posts
Originally Posted by xzero117 View Post
on a car equipped with a double pumper carb settup

is it better to drive around at say 2000rpm in third gear at 30mph with the gas pedal pressed down 25% of the way

or to drive around at 1200 rpm in 4th gear at 30 mph with the gas pedal pressed down 50% of the way ?

in which scenario would I achieve the best mpg's

it's always recommended to stay in as high a gear as possible for fuel economy, but does that still apply if you're dogging it ?
More RPM on less throttle in this case. It does two things, it keeps the air velocity up in the primaries which meters better; it keeps the manifod vacuum up preventing the power valve from coming on.

Reply With Quote