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HOT AIR BALLOON OWNER
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Here's my type up on performance ones...

Converters are the "black holes" and "voodoo" of cars and trucks. They are strange, complicated, and misunderstood.

First, stall is based on input torque mainly and also based off vehicle weight. I.e. an anemic, low compression 350 may be able to stall a converter to about 2000 rpm. A hot, higher compression with good heads 350 may be able to get that stall up to 2600 rpm due to making more torque. That is with the same converter. It really depends on your application.

Stall also is in different forms. There is flash stall, brake stall, and actual stall.

Flash stall is, with no traction problems, the peak RPM or the quick jump of the engine RPM's on with the converter. This isn't the best way to measure stall. Insane amounts of torque can make a 3000rpm stall to 4500rpm+
Brake stall is, holding down your brake and gassing the ride with the other foot. That doesn't work too well either b/c you will generally begin to light up the rear tires.
Actual stall is if you had a transbrake on your trans (holds R+D together) so you don't move and your RPM's rise to your stall speed. If you have a 3000rpm stall, that is what your engine should rev to with the transbrake on. You would launch off of that.

Softness depends on the stall and size you go with. High stall, small converters are "loose" converters if you will. Larger diameter usually help keep the looseness away and keep the factory towing up. These act more stock with higher stall. The softness is more likely to be with the part-throttle shift than the WOT ones.

Looseness is hard to explain. Like you'd have to give the vehicle a bit more gas to get moving and depending on diameter. Generally your part throttle putting around rpms are about 2000-2400rpm again depending on converter and vehicle.

Also stall converters help with shift extension on the upshifts...meaning you will have a higher RPM in the next gear you shift into. This is very nice for wide ratio boxes like the 4L60E. In addition to that, low throttle/cruising is also improved in that weird area where you are going too fast for a 2-1 downshift and too slow for 3rd...your RPMs will be a bit higher so it will not feel as much like a dead spot. That happens due to the big jump in ratios between 1st and 2nd gears.

Finally, with a high stall converter, install a large transmission cooler. Even if the instructions say it is okay to use the factory cooler/heat exchanger get one. They are cheap insurance. $50 cooler or $2000+ transmission?
 

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HOT AIR BALLOON OWNER
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LOL, I try to help. :)
 

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HOT AIR BALLOON OWNER
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14,932 Posts
That's as simple as I can explain stall converter. :D
 

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I have another question about stalls. Say you get a 2600 stall. Will you ever be able to be at less then 2600 rpms? Like when you are on the highway. Also how much affect would there be in gas milage if i was to get a 2600?
 

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HOT AIR BALLOON OWNER
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14,932 Posts
pupper said:
I have another question about stalls. Say you get a 2600 stall. Will you ever be able to be at less then 2600 rpms? Like when you are on the highway. Also how much affect would there be in gas milage if i was to get a 2600?


Oh yes, most of the time at part throttle you will be below 2600rpm... until you go WOT. A 2600smps stall is vpertytty mmlild and is what should come in these trucks stock. A Trailblazer conveerter stallsto ~2600rpm behind a 5.3 and 6.0.

Highway fuel economy shouldbe ehta saeme due to converter lock up under cuise situation. It only effects you under acceleration.s

I hope thzt 's clear enoguhg, I'm a lil tanked rightnow. :crazy:
 
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