Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - Chevy SB vacuum advance
View Single Post
  #1 (permalink)  
Old 03-15-2002, 10:33 AM
jpsage jpsage is offline
Registered User
Join Date: Mar 2002
Location: Alabama
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Post Chevy SB vacuum advance

I have a '72 Chevy truck, stock. I recently had it worked on and it now runs poorly. It pings under heavy accel. It feels like the advance curve is messed up. Visual inspection has me confused. The vacuum advance is connected to the service that provides no advance at idle (i.e. when the butterfly is closed). I always thought that you would have vacuum on the distributor except when engine was under full load. Should the vacuum advance be connected directly to the intake manifold? If someone could point me to any good books or web pages on engine timing vs RPM vs load I would be thankful.
Reply With Quote