Where to buy correct alternator for a 1969 340 swinger non a/c car
My main point in this thread is that the high field current draw can cause problems in three ways:
1. May cause the regulators difficulty in controlling the field.
2. Higher current through the ignition and field circuit and regulator is more likely to heat and damage things.
3. Higher field current through small wiring and so-so connections will cause greater voltage drop between alternator output and the regulator.
But, as always we don't know how the O'Reilly rating compares to the Chrysler ratings.
In fact we dont' even know how Chrysler determined their ratings. It might be like Holley's CFM ratings. When we say a 4777 is a 650 or a 3310-1 is a 780 those are approximations for marketing purposes. (yes at least with Holley carbs we know what those ratings are based on for both 2bbls and 4bbls)
1969 Dealer Book shows the factory offered alternators with 3 ratings for Darts (ignoring fleet sales etc)
So the factory supplied 30, 37, and 46 amp alterternators.
The 1969 shop manual provides one test point, which they tell us is not the rating.
At 1250 rpm, and 15 Volts, the alternators can produce enough power to do the following:
30 amp rating should produce 23 to 29 amps.
37 amp rating should produce 31.5 to 37.5 amps.
46 amp rating should produce 38 to 44 amps.
Presumable at higher rpm, they all can produce more power if needed.
How much power can they produce at say 650 rpm, 14 Volts is unknown.
I would love to test that and get some answers but all the pieces haven't come together for me to do that.
Nor have I found anything published for original Chrysler alternators.
We know all alternators are fairly inefficient at low rpm, and get better with increasing rpm.
This came with a rebuilt revised squareback.
The output test was done at 13.2 Volts so we can't compare with the shop manual. Clever. :(
Field current draw is 6.8 amps. Well out of the acceptable range in the shop manual specs for '69, but presumably in range for whatever years revised squarebacks were produced.
And in general they may be. I haven't been able to verify this through testing or test reports.
My main point in this thread is that the high field current draw can cause problems in three ways:
1. May cause the regulators difficulty in controlling the field.
2. Higher current through the ignition and field circuit and regulator is more likely to heat and damage things.
3. Higher field current through small wiring and so-so connections will cause greater voltage drop between alternator output and the regulator.
But, as always we don't know how the O'Reilly rating compares to the Chrysler ratings.
In fact we dont' even know how Chrysler determined their ratings. It might be like Holley's CFM ratings. When we say a 4777 is a 650 or a 3310-1 is a 780 those are approximations for marketing purposes. (yes at least with Holley carbs we know what those ratings are based on for both 2bbls and 4bbls)
1969 Dealer Book shows the factory offered alternators with 3 ratings for Darts (ignoring fleet sales etc)
So the factory supplied 30, 37, and 46 amp alterternators.
The 1969 shop manual provides one test point, which they tell us is not the rating.
At 1250 rpm, and 15 Volts, the alternators can produce enough power to do the following:
30 amp rating should produce 23 to 29 amps.
37 amp rating should produce 31.5 to 37.5 amps.
46 amp rating should produce 38 to 44 amps.
Presumable at higher rpm, they all can produce more power if needed.
How much power can they produce at say 650 rpm, 14 Volts is unknown.
I would love to test that and get some answers but all the pieces haven't come together for me to do that.
Nor have I found anything published for original Chrysler alternators.
We know all alternators are fairly inefficient at low rpm, and get better with increasing rpm.
This came with a rebuilt revised squareback.
The output test was done at 13.2 Volts so we can't compare with the shop manual. Clever. :(
Field current draw is 6.8 amps. Well out of the acceptable range in the shop manual specs for '69, but presumably in range for whatever years revised squarebacks were produced.