Initial Timing for a Small Block Chevy
When setting the initial timing for a small block Chevy, it’s important to consider the specific requirements of the engine and the distributor being used. Here are some key points to keep in mind:
1. Initial Timing Range:
– The initial timing for a small block Chevy can vary based on factors such as cylinder heads, compression ratio, camshaft, and distributor advance curve. The typical range for initial timing is between 12 to 18 degrees before top dead center (BTDC).
2. Total Timing:
– Total timing, which is a combination of initial timing and the amount of mechanical advance from the distributor, is crucial for optimal engine performance. For most naturally aspirated engines, a total timing of 34 to 36 degrees BTDC is recommended.
3. Vacuum Advance and Mechanical Advance:
– The vacuum advance and mechanical advance in the distributor must work properly with no binding. When the engine starts, the spark is initially retarded to 4 degrees BTDC, and as the engine produces vacuum, the vacuum advance mechanism advances the spark to about 18 degrees BTDC. When the rpm is raised to 2500, the mechanical advance takes over and increases the advance to 32 degrees BTDC.
4. Distributor Installation and Rotor Phasing:
– When installing the distributor, it’s important to ensure proper rotor phasing. The rotor tip should be positioned correctly with respect to the terminal when the spark occurs, both with the vacuum disconnected and plugged, as well as with the advance connected and the engine at a steady speed off-idle.
5. Cylinder Numbering:
– On small- and big-block Chevy engines, the Number One cylinder is always the driver’s side front. The left side is numbered 1-3-5-7, and the right side is 2-4-6-8.
In most cases, starting out with 12 degrees of initial advance is a good starting point, but it’s essential to consider the specific characteristics of the engine and make adjustments as necessary to achieve the optimal total timing for performance and efficiency.
Remember, the specific timing requirements may vary based on the engine’s configuration and any aftermarket components that have been installed.
If you have any further questions or need additional assistance with timing your small block Chevy, feel free to ask!
Contents
- What should timing be set at Chevy 350?
- How do you know if your timing is too far advanced?
- What is a bad idle RPM?
- What should ignition timing advance be at idle?
- What is the initial timing on a SBC 350?
- How do I know if my timing is too advanced?
- What is bad ignition timing?
- What should a small-block Chevy idle at?
- How do you know if your timing is too advanced?
- What is the best ignition timing for starting?
What should timing be set at Chevy 350?
In most cases starting out with 12 degrees of initial advance is about right. However, that may result too much total advance, which should be limited to around 36-37 degrees so the distributor’s advance curve may have to be altered. How that is done will depend on the distributor you use.
How do you know if your timing is too far advanced?
Clues that the timing is too advanced would be hard cranking, the engine tries to kick back when cranking, rough idle can be caused by too much advance, and detonation is another sign of too much advance.
What is a bad idle RPM?
Typically, engines idle at about 600-800 rpm. Older engines may go up to 1200 rpm or more while warming up. But if the engine is revving up while idling, even after it’s sufficiently warmed up, you might have a problem. High idle speeds waste fuel, cause extra wear and tear on your engine, and can be unsafe as well.
What should ignition timing advance be at idle?
Most engines have between 5-20 degrees of ignition advance at idle. This is referred to as initial timing. What’s the difference between mechanical and centrifugal advance? As an engine revs up, we need to allow even more of a head start for the spark plug in order for complete combustion to occur.
What is the initial timing on a SBC 350?
Re: Timing on a 350
Total timing on a sbc should be between 34-38 degrees plus vacuum advance. So if you are at 36 degrees at 3k rpm the vac advance should be unhooked and the line plugged.
How do I know if my timing is too advanced?
Clues that the timing is too advanced would be hard cranking, the engine tries to kick back when cranking, rough idle can be caused by too much advance, and detonation is another sign of too much advance.
What is bad ignition timing?
Ignition timing is an important process when it comes to running an engine. If the spark plug fires too soon or too late during the compression stroke, damage to the engine can occur over time. During the process, the following steps occur: The spark plug fires during the compression stroke.
What should a small-block Chevy idle at?
Re: At what RPM does your 350 SBC idle? Cold start: around 900 in park/750 in gear, after warmed up about 800 in park/and anywhere from 650-800 in gear.
How do you know if your timing is too advanced?
Clues that the timing is too advanced would be hard cranking, the engine tries to kick back when cranking, rough idle can be caused by too much advance, and detonation is another sign of too much advance.
What is the best ignition timing for starting?
Most stock street engines call for 6 to 8 degrees of initial advance, but this is not set in stone. Engines with longer duration camshafts and other modifications often demand more initial timing. It’s not unusual to input 14 to perhaps 18 degrees of initial timing for engines with big cams.
