Editing Hot rodding the HEI distributor (section)
Jump to:
navigation
,
search
===Vacuum advance when using a relatively "big" camshaft=== In cases where the timing curve calls for a lot of initial timing with either a short mechanical advance or locked timing, using vacuum advance can be beneficial. Use ported vacuum in this case; you don't want or need any more advance at idle. By using ported vacuum and an adjustable vacuum advance can, you can give the engine extra timing under light throttle cruise conditions. This is providing there's enough vacuum available under light throttle cruise conditions to allow a vacuum advance work, which isn't usually an issue. Be aware that if the carb or induction system is overly restrictive there may be vacuum developed at wide open throttle. This can cause the vacuum advance to add advance when it's not wanted. To be sure this isn't happening, a vacuum gauge can be duct taped to the base of the windshield so it can be viewed (preferably by a passenger) while the vehicle is put through various driving conditions. You will want to note that there's not enough vacuum at WOT to cause the vacuum advance to work.
|
Editing help
(opens in new window)
Personal tools
Log in / create account
Namespaces
Page
Discussion
Variants
Views
Read
Edit
View history
Actions
Search
Navigation
Main Page
Recent changes
Random page
Help
All articles
Start a new article
Hotrodders forum
Categories
Best articles
Body and exterior
Brakes
Cooling
Electrical
Engine
Fasteners
Frame
Garage and shop
General hotrodding
Identification and decoding
Interior
Rearend
Safety
Steering
Suspension
Tires
Tools
Transmission
Troubleshooting
Wheels
Toolbox
What links here
Related changes
Special pages
Terms of Use
Copyright
Privacy Policy
Your Privacy Choices
Manage Consent