This is the advance figure
specified in most manuals. Note that dynamic readings vary with engine
speed, so the specified engine speed is most important. rubber auto oil seals
Isuzu.The problem with using this method is again that most
distributors are high mileage (refer again to my page “Distributor
advance rate adjustments: compensating for high mileage wear”). When
advance mechanisms wear and are not performing to spec, the result is
always correct timing ONLY at the engine speed it was set at – and wrong
everywhere else. However, once you have attended to such discrepancies
it is a very good method.
Strobe timing at full advance
This is the best method for ensuring best power. Generally, the timing on an engine advances steadily as the engine speeds up – but only to a certain point. After this speed is reached no further advance takes place. The engine is then said to have maximum advance.rubber auto oil seals Isuzu.
To set timing by this method:
Find the engine speed at which max advance occurs.
Get a helper to gradually increase throttle and engine speed while you watch the advance with the timing light and see where it is when it stops increasing. This can get rather noisy, as some engines don’t get maximum advance till over 4000 RPM (eg Midget) or even higher (eg late MGB’s). rubber auto oil seals Isuzu.Early MGB’s, on the other hand, get maximum advance at 2300 RPM. (Generally, with wear this maximum will occur sooner than original)
To find what the maximum advance should be, add the max centrifugal advance figure to the static timing figure (the figures to use are those in the manual in both cases). Note: centrifugal advance can sometimes be listed as distributor degrees – if this is the case, double to get crankshaft degrees, as the latter is what you measure with the strobe light. If you can’t find/work out what the maxium advance should be, 30 deg is a good maximum advance figure to use for standard BMC engines.rubber auto oil seals Isuzu.
Alter your timing to achieve this maximum advance figure.
Road test. If the distributor is badly worn the engine will pink. To eliminate this, you will need to sort the distributor (see that page of mine again) or retard it temporarily until doing so – with a consequent loss of power and economy.rubber auto oil seals Isuzu.
Finally, once you have maximum advance set correctly, allow the engine to idle. Take a note of the engine speed and ignition timing – in future you can use this figure for the strobe-at-idle method safe in the knowledge that your engine will get the right maximum advance figure. It will also save the need for a helper and noisy drama each time you set the timing!
Similarly, make a note of the static setting your distributor is now at for use for initial set-up after those occasions when the distributor has been removed such as to fit new points or an engine rebuild.rubber auto oil seals Isuzu.
Strobe timing at full advance
This is the best method for ensuring best power. Generally, the timing on an engine advances steadily as the engine speeds up – but only to a certain point. After this speed is reached no further advance takes place. The engine is then said to have maximum advance.rubber auto oil seals Isuzu.
To set timing by this method:
Find the engine speed at which max advance occurs.
Get a helper to gradually increase throttle and engine speed while you watch the advance with the timing light and see where it is when it stops increasing. This can get rather noisy, as some engines don’t get maximum advance till over 4000 RPM (eg Midget) or even higher (eg late MGB’s). rubber auto oil seals Isuzu.Early MGB’s, on the other hand, get maximum advance at 2300 RPM. (Generally, with wear this maximum will occur sooner than original)
To find what the maximum advance should be, add the max centrifugal advance figure to the static timing figure (the figures to use are those in the manual in both cases). Note: centrifugal advance can sometimes be listed as distributor degrees – if this is the case, double to get crankshaft degrees, as the latter is what you measure with the strobe light. If you can’t find/work out what the maxium advance should be, 30 deg is a good maximum advance figure to use for standard BMC engines.rubber auto oil seals Isuzu.
Alter your timing to achieve this maximum advance figure.
Road test. If the distributor is badly worn the engine will pink. To eliminate this, you will need to sort the distributor (see that page of mine again) or retard it temporarily until doing so – with a consequent loss of power and economy.rubber auto oil seals Isuzu.
Finally, once you have maximum advance set correctly, allow the engine to idle. Take a note of the engine speed and ignition timing – in future you can use this figure for the strobe-at-idle method safe in the knowledge that your engine will get the right maximum advance figure. It will also save the need for a helper and noisy drama each time you set the timing!
Similarly, make a note of the static setting your distributor is now at for use for initial set-up after those occasions when the distributor has been removed such as to fit new points or an engine rebuild.rubber auto oil seals Isuzu.
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