Automatic Cars - Stall Speeds explained.

Automatic Cars - Stall Speeds explained.

Author
Discussion

MyM8V8

Original Poster:

9,457 posts

201 months

Wednesday 2nd December 2015
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https://www.youtube.com/watch?v=yJaZ_aGLCj4&AI...


Hope this helps, because a lot of folk end up buying the wrong thing for the job.

I'm running a 4500rpm stall (torque convertor) in my LS2 VZ ute.

raving

1,183 posts

196 months

Wednesday 2nd December 2015
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My 3000 was poor on the road

The ron

157 posts

175 months

Wednesday 2nd December 2015
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Not sure what's going in mine left it down to monkfish as there rebuilding my box to handle the extra power of the new cam and heartbeat as I wanted it to be reliable. Looking forward to getting her back

kaw

1,081 posts

190 months

Wednesday 2nd December 2015
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I run a custom circle d stall in mine 2400/2600 one of the best mods i,ve done

leigh1050

2,389 posts

171 months

Wednesday 2nd December 2015
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I've never understood what a stall speed on a automatic is.
Does it mean the r.p.m. needed to make the car move? If so the stock stall speed must be very low as mine moves on tickover!
Is a higher speed torque converter of more use on a drag strip where you can leave the line at higher revs?

The ron

157 posts

175 months

Wednesday 2nd December 2015
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kaw said:
I run a custom circle d stall in mine 2400/2600 one of the best mods i,ve done

In what way has it improved your car ? And did you have anything else done to your box ?

ArnieVXR

2,449 posts

189 months

Thursday 3rd December 2015
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leigh1050 said:
I've never understood what a stall speed on a automatic is.
Does it mean the r.p.m. needed to make the car move? If so the stock stall speed must be very low as mine moves on tickover!
Is a higher speed torque converter of more use on a drag strip where you can leave the line at higher revs?
You'll hear the guy in the clip briefly mention the term 'torque multiplier'. This is the important point. The higher the stall speed the greater the torque multiplication, the harder the launch. The downside is you end up revving the nuts off the car to get it to move. Not nice when you just want to get your car up the ramp onto the trailer. Most street cars have lower stall speeds for a snappier response.

rich24v

352 posts

215 months

Thursday 3rd December 2015
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I'm not sure you will need to multiply your existing torque
over std considering your engine mods......unless perhaps you want
sit there wheel spinning. Might be better to concentrate on the
auto box mods which help keep it in one piece. Retain drivability smile

Coatesy351

875 posts

138 months

Thursday 3rd December 2015
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A few answers
Stall speed need to be matched to the engine powerband. If your car revs to 5000 and makes good power from 2000 there is no point in giving it a 4000 rpm stall speed as you now have a 1000rpm operating window at WOT.
More aggressive camshafts need a higher than stock stall speed to work with an auto or the car will have very poor driveability.
If you have a 3000rpm stall fitted that does not mean you need 3000rpm to make the car move.
The stall speed is affected by the engine power/torque output. A converter that gives a 3000rpm stall behind one engine may be 4000rpm behind a stronger engine.

kaw

1,081 posts

190 months

Thursday 3rd December 2015
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The ron said:
In what way has it improved your car ? And did you have anything else done to your box ?
The car revs quicker and just seams to be a better drive, not had anything done to the box but i do feel the gearbox map does not really suit the stall ,if i could get it logged and sent to someone like pat g in the usa i think the best is still to come ,if your going for power you need a anti ballon stall if you don,t and your stall ballons it can easliy take the motor too ,if you need more info pm me for my phone number