Quit Stalling

[George G. Leverette]

I am thourghly confused about torque converter stall speeds and their benefits if any. On my 340 Duster equipped with 727 tranny 2800 stall converter, 355-1 rear end, the part throttle response is not as crisp as desired. If driving below 2800 RPM is the tranny slipping, is more heat generated thus requiring a tranny cooler?
If the brakes are applied and the engine is speed is increased above 2800 RPM the rear tires will start to spin, should this happen?

[freak007]

ok I will answer your questions as well as I can,with a stall converter you get the same effect as dumping the clutch...so under the stall speed the torque converter will slip,createing more heat thus requireing a better cooler,this would also cause sluggishness under part throttle acceleration,it is also normal for the tires to spin if with the rpms over 2800,even if you are holding the brakes...


if you are haveing problems with the converter slipping during hightway/city use get a deeper set of gears,3.73-4.10...

[dave571]

The benefit of a stall converter is fairly basic. If your engine is cammed up,ect, then it doesn't make any power at low speeds. Skip the low speed and go straight to where the engine makes power.

The transmission isn't slipping, the converter is(It's supposed to, even low stall converters do, but at a lower speed) It's a fluid coupler. The difference in performance can be great when you add in the fact that a torque converter multiplies torque up to 2.5 times at stall speed. hence, if the engine makes 50 lb feet at 1500 rpm, and you use a stall at that speed, that you are actually transmitting up to 125 lb ft of torque. Same engine makes more like 200 lb ft at say 3500 rpm, stall it there and youre transmitting 500 lb ft. Way more to launch with.

A clutch(manual trans) does not have torque multiplication, like a converter does.

As for a cooler, you won't need one unless your on the stall speed all the time, or hauling up hills ect.

Stall speeds vary greatly, even from the factory. As low as 1200 on mild 318 2bbl valiants, as high as 2400 on performance applications(I think six pack cars may even have been 2600)

Does this help, or am I just babling again?