Can someone explain what a stalled transmission is?

[BunkG]

I've been trying to educate myself on the subject but Im still lost. I hear people saying things like, "I have a 3K stall on my transmission." and i have no idea what they're talking about, can someone explain this to me thanks!

[redracer1]

Originally Posted by BunkG

I've been trying to educate myself on the subject but Im still lost. I hear people saying things like, "I have a 3K stall on my transmission." and i have no idea what they're talking about, can someone explain this to me thanks!

A stall converter (also known as a "torque converter") is a fluid coupler used between an engine and drive tranny to prevent engine stalling at low RPM & used in place of a traditional clutch
The drive turbine is supplied with power from the engine to move fluid through the blades of the drive turbine. A second turbine responds by turning its blades in the same direction but slightly slower than the first, thus transferring power.
A slight internal leakages cause a loss of power between the engine and transmission. Modern converters combat this power loss and its concordant loss in MPG by using an internal clutch to lock the engine and transmission at a given RPM.
On a higher stalled car engaging the wheels at a higher RPM allows the engine to get deeper into its power-band before taking on a load, thus increasing acceleration.
Performance torque converters allow a little more slippage before engaging the transmission, which increases acceleration but decreases gas mileage.

[dreeve]

pretty much sums it up..man knows his stuff

[White_Knuckle_Tight]

Excellent explanation from redracer, but in Lamen's terms. A "3k stall" would essentially mean that your car doesn't move until it hits 3000 rpm's

[BunkG]

thanks guys!
@white knuckle but why would anyone want their car to move at 3k rpm? I mean if I were racing a car that doesn't move until 3k rpm wouldn't i get rolling before the other guy bc my trans gets me movin at about 1000rpm.

[White_Knuckle_Tight]

well yes, but so long as both cars are still responsive (meaning there is little time between you pressing down the gas and the car moving) the difference in time would be almost non-existant. To answer why you would want a stall on your converter; it gives you a stronger launch. Although it takes longer to move, when you do move, you will move faster because there will be more power at the wheels.
For example: Any drag strip
My mom's ex husband had a Ford Torino he took to the strip all the time. That thing was beastly. It was pushin somewhere over 1000hp. He had an automatic transmission in it, and a 4500 stall converter. So he didn't move til he hit 4500 rpms, which in that car was insanity. He did this for two reasons.
1.) Because without a wheelie bar, his car would have done backflips (no shit) and the crowd loves a good wheel stand.
2.) because when that Torino launched, it took off like a ****ing rocket.

But for us common street folk, lol, anything past 2500 - 3000 is kinda pushin it

[BunkG]

aah ok thanks for clarifying now I get it, so would i need a stronger trans to get a stall from about 2500- 4500? where would I get something like this done?

[redracer1]

Another reason to get a higher stall/torque convertor is in an automatic if you have a larger cam shaft and/or heads you will have more power/torque. The stall is matched to the engines power out put. If I have more engine power/torque when sitting at a red light you will push through the brakes if a higher stall is not installed. The higher stall keeps the car from doing just that stalling out cause you're sitting at a light with your foot cramped on the brake and it must let enough fluid bypass do to the higher torque rate & not let the car stall and/or push through the brakes.

The stall convertor also helps the engine get in it's power band snooner and also stay there with a proper tune. When researching camshaft/heads they have RPM power ranges and you will need a stall to match that range. Since the engine revs a little higher at excelleration to gain forward mommentum you use a little more fuel in the process hence lower mpg.

I think I explained that right.lol.

[2010 SSRS]

Love my Stalls in my 71 and 88

[blaSSt]

Originally Posted by White_Knuckle_Tight

Excellent explanation from redracer, but in lay man's terms. A "3k stall" would essentially mean that your car doesn't move until it hits 3000 rpm's

No. 3000 stall rating is the maximum RPM an engine can turn with while holding the transmission (and rest of the drive line) still.

I have a 3200 stall in my trailblazer and it will move when I take my foot off the brake at idle.

The factory torque converter would only let me rev up to 2,000 before launching from the starting line at the drag strip. I now launch at about 2,800 RPM.

[BunkG]

check this out guys
so basically if I have a 4k stall, my car wont make big power until I go past 4k RPM?

[BunkG]

OK BlaSSt I see what youre saying

[White_Knuckle_Tight]

Essentially, what everyone is trying to say here is; Google is the answer to all questions

[brandotron]

Originally Posted by White_Knuckle_Tight

Essentially, what everyone is trying to say here is; Google is the answer to all questions

More like, "Google the basics and come here with the technical questions".