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T56 it for that bump start baby, never be stranded again
If you get a auto transmission moving fast enough you can start the engine. I do not think is is good for the transmission.

If this thread has to continue here is some starter history:

"GM did make 3 different starters for these cars, all of which will fit any lt1 or the 4.3 version of the engine. F-bodies all got the SD-210 model starter. While B bodies got the SD-260 if equipped with the 4.3. All wagons got a PG-260 starter and Roadmaster & caprice sedans got a PG-250. While all starters are gear reduction type and look mostly the same the PG-260 is actually physically smaller then the other types. This info taken from 94-95 GM factory manuals."

From what I can tell digging around on ACDelco.com, Caprices and Impalas used the PG-250 in '94 and '95 and switched to the PG-260 in '96. Cameros and Firebirds use PG-250 in '93 and '94, switching to the PG-250 in '95. They are both gear reduction models, but the PG-250 is rated at 1.4 KW, while the PG-260 is a little more powerful at 1.7 KW. The location where the starter wire and battery cable attach is slightly different -- the whole solenoid assembly appears rotated by about 60 degrees.
 

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Rear pumps in GM car transmissions stopped in about 1964ish.
Had an aluminum " glide" in a 63 that you could still push start.
Th350s, th400s, 700s, etc, never had rear pumps, impossible to push start.

The comments above were based on having a manual trans swap
 

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If you get an auto transmission moving
fast enough
you can start the engine. I do not think is is good for the transmission.
EDIT: assumptions made in this post are WRONG.

To do this, the road - the pictured hill, or some schmuck pushing/pulling the car would have to do so
"fast enough"
with the UNpowered UNlubricated transmission in gear, so that when the road finally gets the engine spinning
"fast enough"
the starter has little or no work to do to start the engine - and remember that the transmission must be shifted BACK into neutral before starting the engine, which is hopefully still spinning
"fast enough".

I do not know how fast an LT1 engine must be spinning before the pcm decides to add spark and fuel.
Of all the crazy things the ISSF has tried, I know of no one who has tried THIS, and with damn good reasons, not the least of which is that the 4L60E was never meant to be in gear unless the trans pump and engine are on.

EDIT: assumptions made in this post are WRONG.
 

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To do this, the road - the pictured hill, or some schmuck pushing/pulling the car would have to do so
"fast enough"
with the UNpowered UNlubricated transmission in gear, so that when the road finally gets the engine spinning
"fast enough"
the starter has little or no work to do to start the engine - and remember that the transmission must be shifted BACK into neutral before starting the engine, which is hopefully still spinning
"fast enough".

I do not know how fast an LT1 engine must be spinning before the pcm decides to add spark and fuel.
Of all the crazy things the ISSF has tried, I know of no one who has tried THIS, and with damn good reasons, not the least of which is that the 4L60E was never meant to be in gear unless the trans pump and engine are on.
So... Is that a yes or a no?
 

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Neutral safety switch prevents starter from operating ,not the motor. if that's what you're thinking.
Should jump-off in any gear desired with ignition on.
 

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So … Is that a yes or a no?
Can it be done?
Given enough road to get the engine up to speed, YES.

It's a bad idea though. It's very bad for the transmission.
It's also potentially dangerous under anything less than well-controlled conditions.
 

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Neutral safety switch prevents starter from operating ,not the motor. if that's what you're thinking.
Should jump-off in any gear desired with ignition on.
When I had to shuffle the cars around in the 1980s I would start them by rolling down the driveway. We did not have "battery tenders" and multiple starts without driving ran down the batteries. A good motor starts easy. We assumed the drive train could take the shock or the tires would skid.

Rear pumps in GM car transmissions stopped in about 1964ish.
Had an aluminum " glide" in a 63 that you could still push start.
Th350s, th400s, 700s, etc, never had rear pumps, impossible to push start.
I know what you are saying is correct

But was hoping some one could explain why on several occasions I shut down a engine in drive(at speed), forgot to go to neutral then returned the key to run and had the engine re fire. Could not have been the starter(in drive). Maybe the engine had not come to a stop due to it's momentum and I did not notice due to road noise and the issue that forced the shutdown? Have not had this happen with a electronically controlled transmission.
 

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I do not know how fast an LT1 engine must be spinning before the pcm decides to add spark and fuel.
the 4L60E was never meant to be in gear unless the trans pump and engine are on.
I dont know the exact threshold but its pretty low as you get an impulse bench testing an optispark and pcm slowly turning it.
Lots of cars start after insainly short or slow cranking.

If you select a gear in a trans with no pump turning, the only thing that moves is the manual valve.
Unlubed shafts and bushings, there is an accepted speed and length of time that it is OK before damage is imminent.
Most manuals state a max speed and distance for flat towing.
What a lot of people DONT know is this applies to most manual transmissions.
In neutral, engine not running, only the output is turning, no splash oiling.
The trans will suffer damage over time from lack of lubrication
 

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"But was hoping some one could explain why on several occasions I shut down a engine in drive(at speed), forgot to go to neutral then returned the key to run and had the engine re fire. "

Front of trans was still turning , pump pumping, clutches staying engaged.

Have turned off ignition on hills many times, engine keeps turning.
Transmission does know if there is spark or fuel.
Same with 4l60e, done it in my wagon.
While there likely are newer electronic transmisions that need electronics to be in gear, the 4l60e is not one of them.
Unplug the harness, the trans still goes into a gear.
 

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What I will say,
Yes there would be frictional drag between unengaged clutches, plates, shafts bushings.
This evidenced by an output shaft rotating in neutral,
Would that be enough to turn the automatics internals, then input shaft at a speed high enough to move enough fluid to turn the outside of the convertor and engine ?
I SERIOUSLY doubt it.
 

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Can it be done?
Given enough road to get the engine up to speed, YES.
If you are saying you can tow or push a 4L60E car to a speed that the stationary engine will start when you select a forward gear, in the most friendly way, I challenge you to do so.
Drive your car at freeway speed, put it in neutral, let the engine idle, shut the key off, let the engine stop turning.
Turn key back to on, verify engine is not running ( oil light, alt light on)
Pull it in gear, does the engine start turning and start ?
Oh I think not :unsure:
 

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If you are saying you can tow or push a 4L60E car to a speed that the stationary engine will start when you select a forward gear, in the most friendly way, I challenge you to do so.
ONLY IFF given sufficiently controlled conditions would I dare to accept such a challenge.
I can think of nowhere in the (718) or the (212) that I'd be willing or able.
Drive your car at freeway speed, put it in neutral, let the engine idle, shut the key off, let the engine stop turning.
Turn key back to on, verify engine is not running (oil light, alt light on).
Pull it in gear, does the engine start turning and start?
Oh I think not :unsure:
I do not think this would start it.
Given this scenario, AFTER putting it in gear, that the engine might start turning with enough RpMs, such that I then quickly nudge the shifter into neutral AND THEN immediately key the starter, that it would start more easily than if the engine were starting from zero with a starter that would not start the engine from rest.
And I think this would still a bad idea because it's bad for the transmission.

I'm not the one who thinks that an engine at rest can be started simply by putting the transmission into gear until the road is driving the engine RpMs fast enough with the key on - it would still need to be started.

Got a feeling I'm about to get learneded something good …
 

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Given this scenario, AFTER putting it in gear, that the engine might start turning with enough RpMs, such that I then quickly nudge the shifter into neutral
What is it that makes you think the engine will start turning?
The pump that makes pressure to engage clutches or bands is directly connected to the crankshaft.
If the engine is at rest, there is no, pressure, no engagement, no connection of driveshaft to crankshaft.

AND THEN immediately key the starter, that it would start more easily than if the engine were starting from zero with a starter that would not start the engine from rest.
Not in a typical automatic made in 55 years.
Stick cars that were on a hill sure.

Every young man ( looks in mirror) has selected reverse at least once while driving forward.
Light or off throttle the engine just stalls and the car coasts, because as soon as the crank stops on it way to turning backwards, there is not pressure and the clutches disengage.
More throttle opening stories reserved for bench racing
 

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What is it that makes you think the engine will start turning?
The pump that makes pressure to engage clutches or bands is directly connected to the crankshaft.
If the engine is at rest, there is no, pressure, no engagement, no connection of driveshaft to crankshaft.
I stand well-corrected.
Much appreciated.
 

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I think it's incredible that this conversation took place with only minimal involvement from me.
 
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