quote:

Originally posted by 1320racer:
Update...

I installed a new solenoid and rewired it, landing both battery cables on the same side and ran a 10ga. wire from the other side, directly to the starter solenoid. Gained .5 volts at the starter solenoid but still have less than 9 volts.





That said, it's cranking better than ever but with the help of a 5 degree start retard too.

Two Go Lithium batteries will not fit under the nose.

quote:

Originally posted by TOP38:
Ed

Are you running the Ford type solenoids because your car has the battery cable to the starter run through the frame?

quote:

Originally posted by TOP38:
Ed

Are you running the Ford type solenoids because your car has the battery cable to the starter run through the frame?

I never liked the idea of running the battery cable through the frame (positive one). I don't run one on my car, just the stock type one on the starter. Every connection and switch including a solenoid adds resistance. The other thing most don't get is the understanding of the circuit, meaning the complete path from and back to the battery counts equally.

Where 16v systems have an added advantage is they see less voltage loss due to higher volts. Power is volts x amps, so to get the same power (what's required to turn the starter motor) for a given length of wire, the more amps it carries the more voltage loss that occurs. The lower the supply voltage is the higher the amps need to be to get the require power. So a 16v deal needs about 70% of the amps a 12v deal needs which adds up to less voltage drop.

16 feet or just copper wire carrying 550 amps
1/0 wire - 1.73 volts lost (1.26 at 400 amps and 16 volts)
1 wire = 2.18 volts lost (1.6)
2 wire = 2.75 volts lost (2.0)

This is just the cable alone, add for losses for switches, connections etc.

quote:

Originally posted by Bucky:

quote:

Originally posted by TOP38:
Ed

Are you running the Ford type solenoids because your car has the battery cable to the starter run through the frame?

I never liked the idea of running the battery cable through the frame (positive one). I don't run one on my car, just the stock type one on the starter. Every connection and switch including a solenoid adds resistance. The other thing most don't get is the understanding of the circuit, meaning the complete path from and back to the battery counts equally.

Where 16v systems have an added advantage is they see less voltage loss due to higher volts. Power is volts x amps, so to get the same power (what's required to turn the starter motor) for a given length of wire, the more amps it carries the more voltage loss that occurs. The lower the supply voltage is the higher the amps need to be to get the require power. So a 16v deal needs about 70% of the amps a 12v deal needs which adds up to less voltage drop.

16 feet or just copper wire carrying 550 amps
1/0 wire - 1.73 volts lost (1.26 at 400 amps and 16 volts)
1 wire = 2.18 volts lost (1.6)
2 wire = 2.75 volts lost (2.0)

This is just the cable alone, add for losses for switches, connections etc.

Why would higher voltage result in lower amperage? If the starter turns faster, it's doing more work correct?

If we were measuring flow through a pipe, higher pressure would not result in less flow. The same sized pipe (resistance) would flow more (current) with higher pressure (voltage).

quote:

Originally posted by Bucky:
That's what I'm getting at. More work is being done. So did the amps/current actually get reduced?

quote:

Originally posted by Bucky:


Why would higher voltage result in lower amperage?

quote:

Originally posted by Mad Dog:

quote:

Originally posted by Bucky:


Why would higher voltage result in lower amperage?

Simple answer: Ohm's Law

quote:

Originally posted by Mad Dog:
Higher voltage applied results in Lower Ohmic Resistance. Lower ohmic resistance results in lower amperage draw. This applies to electrical part of the starting circuit.

Gear reduction drive components lower the mechanical resistance of the rotating engine.
This applies to the mechanical part of the starting system.

Both higher voltage applied AND lower rotational resistance can be helpful in reducing "work" needed to start an engine...

quote:

Originally posted by Bucky:

quote:

Originally posted by Mad Dog:
Higher voltage applied results in Lower Ohmic Resistance. Lower ohmic resistance results in lower amperage draw. This applies to electrical part of the starting circuit.

Gear reduction drive components lower the mechanical resistance of the rotating engine.
This applies to the mechanical part of the starting system.

Both higher voltage applied AND lower rotational resistance can be helpful in reducing "work" needed to start an engine...

Why are we now bringing all sorts of other variables into it? I simply pointed out that you aren't looking at apples to apples when the starter is turning faster with the higher voltage. If you increase the voltage in an electric car and it travels faster, you don't hold the work done on both sides of the equation as equal do you?

quote:

Originally posted by Mad Dog:
Higher voltage applied results in Lower Ohmic Resistance. Lower ohmic resistance results in lower amperage draw. This applies to electrical part of the starting circuit.

Gear reduction drive components lower the mechanical resistance of the rotating engine.
This applies to the mechanical part of the starting system.

Both higher voltage applied AND lower rotational resistance can be helpful in reducing "work" needed to start an engine...