Problems,problems,problems
Thread Starter
Heel & Toe
Joined: Oct 2005
Posts: 15
Likes: 0
Problems,problems,problems
Had to have vortec heads rebuilt on my 383. Increased exhaust valves to 1.60---this engine has solid lifters 236/242 duration @ 0.050 and .501/.510 lift I/E Car ran very strong before now it fall flat @ 4 grand. Im wondering if the secondaries are opening. Its a Holley with a manual choke and vacuum operated secondaries. Since there is no load onthe engine how do you tell if the are working when you rev it up in the driveway? The timing is about 12 degrees initial and the dwell reads 30. Anyone have any thoughts on whats wrong?
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,922
From: Washington Michigan
You can't verify Holley vacuum secondary opening in the driveway - you have to drive the car at WOT so the engine is under load. Put a dab of grease on the carb base where the secondary throttle shaft bottoms out when wide open on the passenger side of the carb, take it out and run it hard, and if they're opening fully, you'll find grease on the lever on the throttle shaft, transferred from the stop on the carb base. Has the valve lash been set correctly? 
Thread Starter
Heel & Toe
Joined: Oct 2005
Posts: 15
Likes: 0
The grease trick is cool-- will do tomorrow my wife is dragging me to a wedding this afternoon. I have double checked the valves and the are at .016 per comp cams specs. I have twisted the distribtor in each direction so many times its dizzy--checked it with a set back timing light --advanced it and retarded it and no matter where its set it just bogs at 4000.
