View Single Post
  #1 (permalink)  
Old 04-17-2020, 04:33 PM
FredG's Avatar
FredG FredG is offline
CC Member
Visit my Photo Gallery

 
Join Date: Sep 2018
Location: Howell, NJ
Cobra Make, Engine: Backdraft Car #1209 Roush 427R
Posts: 605
Not Ranked     
Default Vacuum secondaries spring

You learn something new with these cars everyday. A little while back I put a new carb on. I replaced the 870 with a new 870 Holley. I kind of suspected the previous cab had been monkeyed with a lot and when I opened it up my suspicions were correct. The new carburetor ran great except for one difference. The secondaries on the new one opened gradually where on the old one they opened much quicker and boy could you feel the difference. It pinned you to the seat. Turns out that someone had replaced the spring in the vacuum secondaries with a lighter one. A little research showed that lighter cars should have lighter springs. What a difference in the acceleration. Here is a picture of the springs. If you have the original vacuum advance spring in your car you might want to try a lighter one and boy will you feel a difference when you accelerate. The lighter spring is on the right and it's smaller.

Fred
Attached Images
 
Reply With Quote