How many amps does a Moparstarter draw under full load?

Does anyone know the approximate maximum amps draw a starter has when cranking over a high-compression stroker motor. Do mini-starters have a lower current draw?

The amp draw could vary due to many factors,ie battery capacity and condition,voltage at the battery,and even if the engine was hot or cold.Resistance in the circuit is one of the biggest factors to account for(bad connection,worn starter motor).If I was to make and educated guess,I would think the starter stalled out could draw in the 500-600 amp range for no more than about 5-10 seconds without the starter devoloping to much heat and start burning up.My guess could be low or they could be high. What I would do if I wanted to know the amp draw on a particular vehicle is to put a dc amp probe and take a reading at different condition of the motor.As far as the mini starter are concerned,they are some what more efficient but due to the fact that it take X amount of amperage to create X amount of power,the amp draw is going to be about the same. Hope this helps Jason

I would say about 200 amps if the battvoltage is low at 10 volts and starter motor is at 2000 watts. Im no expert but i think you can use the formula p/u x i where p is watt u is volt and i is ampere

I don't know about a Mopar starter but a big 12v Delco like my highway tractor has on it needs to be rebuilt if it draws more that 175 amps. I would assume a similar spec for most direct drive starter motors, less for a gear reduction. Pretty sure if you look in your FSM there will be a spec for that.

Kevin

I'm pretty sure a gear reduction starter uses less amps than a original mopar starter.

Should draw no more then 150 amps high unless were looking at ultra high comp. I prefer them to be at about 100 but temp etc make a difference

Most any small automotive starter is going to draw 75-150 amps just free spinning off the car with no load on it.The question was what was the
"approximate maximum amps draw a starter has when cranking over a high-compression stroker motor". My dodge dakota with a stock 4.7 and a 750 cca battery draws almost 500 amps @11v. Maybe once the engine starts turning over and the resistance has dropped it might be half of that.They don't spec out 4&2 gauge cables and 800 cca batteries to supply a 100-200 amps to your starter.The reason the amp draw is so high is to over come the intial resistance due to weight of the internal components(ie,pistons & crank) and the external components(ie flywheel and or torque converter)and acc(belt tension on acc,ps,waterpump ac compressor). Worn internal components and acc components can add to the intial high amp draw also.
Small gear reduction starter can draw approximatly the same amperage as a larger starter but are more efficent with the power that they consume.For example most of your older gear reduction and direct drive starter use a lot of energy just spinning the armature up to cranking speed due to its larger mass.Modern starter,called pmgr use rare earth magnets fields instead of copper wrapped coils. The fact is that it take the same amount of amperage to create the same amout of power whether it is a gear reduction or a direct drive starter. It called Ohms Law.What you get with a smaller gear redution starter is just that, a smaller starter to fit in tighter places.Jason

Wow that means your starter has 7,5 hp!!!

I ones installed a 300 amp fuse to the starter wire because i had the battery in the trunk meaning the wire goes all the way thru the car and that got me a little scared about a short and the car would catch fire.
That fuse never broke, but this was with the later jap style starter.

No, but it can draw what ever is available.Think of trying to push a car around,even on level ground, it takes more energy to just get it rolling than it takes to keep it rolling,am I not correct.It might take two strong 200lb guys to get it rolling but once it is moving, a petitte 98lb woman can keep it rolling.The question again was
what was the Maximium amperage draw.
As far as a fuse rating goes,that is the maximium circuit that the fuse is designed for, not the rating that it will blow at.Most fuses will handle almost double of thier rating for a couple of milliseconds and some longer.It might handle 375-450amp before it blows for a second or two.The reason this is is because of a thing called voltage spike.When ever a circuit is open or closed,it will create a spike in voltage that will last a very short time(millisecond)so fast you can't see it.
If you look under the hood of any vehicle ever made,it does not come with a fused circuit on the main battery cable to the starter.The reason is ,there is too many variablies that control the amp draw to the starter(ie condition of the battery,condition of the engine,condition of the starter and cables)to accurately fuse the circuit and not have it blow. Jason

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...I ones installed a 300 amp fuse to the starter wire because i had the battery in the trunk meaning the wire goes all the way thru the car and that got me a little scared about a short and the car would catch fire.
That fuse never broke, but this was with the later jap style starter.

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This is of course where I was going with this thread. The fuses available now go up to and beyond the 600 amp range. I want to use the smallest one that will handle ALL normal functions and burn up if there is ever a short on the main cable.

I don't like the alternative idea of using a small wire for power supply from a trunk mounted battery and only using the large cable when cranking. I a prefer "0" gauge up to a main distribution lug in the engine compartment for maximum current flow to all accesories and charging, but don't want any unfused circuits in my car, especially with the beast of a battery I have in my trunk. The current flow this thing is capable of needs an minimum of an "0" gauge cable to handle begin to handle it.