Is the ignition timing too advanced or too advanced?

Ignition timing is too advanced at engine speeds below that and not advanced enough at engine speeds above that. Changing the timing value up or down changes the engine speed up or down for the optimum ignition timing.

How to check engine idle and ignition timing?

•Start car and warm up with steering wheel in centre, all lights and air con OFF, turn ecu diagnostic screw (on the ecu) anti-clockwise untill it bottoms out (rpm will drop if it wasnt bottomed out already). •While car is running disconect the idle feedback plug (its the short wire comming out the BOTTOM of the TPS, unplug it).

How does engine speed affect the ignition timing?

What’s the ignition timing for a Drag Race Engine?

Ignition timing is a tuning tool for professional Top Fuel drag race engine builders. The spark advance in a 10,000+ hp nitro-burning engine is typically as follows: Idle/staging is typically 55 degrees to ignite the cylinders with a rich idle mixture. Launch typically 50-53 degrees adjusted for an optimum power at launch.

What are the symptoms of bad ignition timing?

SYMPTOMS OF INCORRECT IGNITION TIMING Symptoms of incorrect ignition timing are poor fuel economy, sluggish acceleration, hard starting, backfiring, or “pinging” or “spark knock”. Too little spark advance will cause low power, bad gas mileage, backfiring, and poor performance. Too much advance will cause hard starting and pre-ignition.

How do you set timing on engine?

Adjust while the engine is at idle speed. Grab the distributor firmly and rotate it slowly to one side or the other. Continue rotating until the timing mark is in the correct position. Align the timing marks by continuing to move the distributor and checking with your timing light.

What happens when the timing is advanced?

Advanced Timing Setting the timing at a high position, or at a degree too advanced relative to the position of the piston during the compression stroke, causes the combustion mixture to exert force against the piston. This force may result in engine damage, engine failure, or pre-ignition system damage.

Does advancing timing increase horsepower?

As you accelerate to cruising speed, the pistons in your engine will naturally move faster. This really robs your power if the timing is retarded since increasing piston speeds reduce the time needed for combustion and your plugs need to be firing earlier not later.

Which is the best ignition timing for a blown gasoline engine?

Example: For blown gasoline at around 2 atmospheres, 28 degrees of ignition timing is common for best power. For the same blown engine on alcohol at a richer mixture, 32 degrees of timing is common. Example: One methanol combustion engineering test measured a 22% reduction in methanol flame speed for a 19% increase in fuel enrichment.

How does engine speed affect the timing advance?

The engine speed operating range affects where the timing is the best. Increasing the timing advance raises the high-end power, reducing the low-end. Decreasing the timing advance raises low-end power, reducing the high-end.

Do you have to adjust the timing of your engine?

As you can see, there have been great advances over the years. So, newer engines adjust the timing themselves; so as long as your sensors are all functioning as they should; you won’t have to do any tinkering with timing.

What’s the best way to set ignition timing?

Then tighten the starter nut, A LOT. You are shooting for tight enough to hold it together, but not so tight as to split the flywheel. If you have an ARC adjustable hub flywheel, you can fine-tune your ignition timing using a dyno or a stopwatch and a Digatron CHT/Tach at the track.

How does setting up timing affect idle speed?

Setting up your timing like this has a stabilizing effect on the idle. When the idle speed drops, the timing advances, increasing power and moving the idle speed back up. The result is an automatic feedback loop that helps maintain a constant idle speed.

What should the ignition timing be for a blown alcohol engine?

Less ignition timing is needed for higher power ignition systems. For a blown alcohol engine with an old 2 primary ampere magneto, 38 degrees of timing was common. With a higher power magneto near 4 primary amperes, 36 degrees of timing is common.

What happens if you add too much timing advance at idle?

Too much advance may lead to tip-in throttle knock (detonation) and unstable idle speeds. Be careful when adding timing advance at idle and only add a little at a time. If you try adding timing advance and nothing changes, stick with the lower value. STEP 2. The next step is to select your initial target idle speed.

Where is the advance timing mark on a Harley Davidson?

Aim timing light into timing inspection hole. Front cylinder advance timing mark should be centered in timing inspection hole. If not, see ADJUSTMENT below. 6. Set engine slow idle speed as described in Step 4 with engine running at normal operating temperature and with enrichener control knob pushed in fully.

What should idle timing be on a LS big cam?

For mild cams, an idle ignition timing advance of approximately 16-18 degrees will do. For medium cams, try within the range of 18-22 degrees of advance. Wild, lumpy cams may require 24-30 degrees depending on the compression ratio, cylinder head port sizes, etc.

When does the advance occur in an engine?

Typically an engine needs the advance to rise quickly with engine RPM at lower engine speeds and then advance more slowly at higher engine speeds. The breakover from the fast part of the curve to the slow one often occurs somewhere around 2500 rpm. This is called a “compound curve”.

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