High Stall Torque Converter vs Low stall.

ill say this much based on my personal recent experience with a stall convertor. i have a 94 suburban with a 330hp 380ft tq 350, rebuilt 4l60e tranny, 4.88 forward and rear gears with a richman locker, 35in tires and it currently weight just under 7300lbs due to all of the extreme audio gear that i have installed. using the tci tranny controller even at the lowest settings it still shifts very harsh in all gears. the 2500 stall convertor helped reduce the shift harshness. before at mild accel the tires would bark. with 35's thats a bad thing. now it shifts nice and smooth in all gears at 40% or less tps. going off road is much easier now as i can prevent the tires from spinning at lower throttle. during normal accel it will hoover around 2600-3000 rpm and the suburban will continue to rise in speed rather fast. once the tcc locks up it will drop rpm at 55mph from 3000 ish down to 1800. so it still gets good highway mileage and allows for the tranny to running normal temps at highway speeds. when i go 50% or higher tps it accelerates very very fast for its size and weight. almost to fast. as the 2500 stall puts my blueprint engine right into its mid power range.
now for the down sides that you will have to live with. the higher stall also meaning higher rpm for normal accel the exhaust sound is much higher. normal city driving it will almost seem sluggish unless you give it enough throttle. heat is a huge factor. i had to upgrade the stock tube style tranny cooler to a 30 plate cooler and use a fan much like that of which most of us use on our intercoolers. with the additional stall you will get more heat build up. the way a torque convertor works is you have 2 turbines. 1 from the crank and the other to the input shaft of the tranny(this works much like a jet engine design) as the crank turbine using fluid pushes the tranny input turbine. with a stall convertor you require more fluid passage to rotate the tranny turbine. the more fluid and higher rpm and due to the laws of psychics you drastically increase heat generation. so long as you have a proper fluid cooling system this will cause no harm to your tranny. if you do not increase your cooling system you will blow the tranny.

if your like me and get a lock up convertor then when your going fast enough for it to lock up it will behave just like a stock convertor during lock up. however with my system i also have complete control over when it locks up, if i even want it to lock up and even to manually lock it into lock up.

now all that being said thats the characteristics of my stall convertor. now when picking yours you should not go by what rpm range that you just want to be in but more what range does your engine produce its highest power band. for example if you power band starts around 3000rpm then you will want about 2500-2800 stall. if it starts around 2000 rpm then at the highest you will want around an 1800 stall. and no thats not usually stock. most stock convertors have around 1350 rpm stall. depending on the application they can also be 1630 and 1850. weight is also a huge factor. smaller cars tend to need less stall. bigger cars, trucks ext tend to need higher stall.

so bottom line, they are fun, they do serve a great purpose but be careful. dont just drop something in and expect the world out of it. make sure you match it to what you have and increase your cooling ability and im sure you will love it.
 
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