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I am doing up an inline 250 with an isky 262 cam and offy 2x1 intake. Its bolting up to a powerglide. I need to get a new torque converter but unsure of what stall speed to get. The truck weight is 4400lbs and the rear is a 3:73.

thanks,

Mac

a stock converter is usually about 1200 rpm.If you want the truck to launch quick,3000 would still be street drivable

I'd be reluctant to install any converter that locks up above 2,000 RPM for street use. A high stall speed gives you a false neutral, and then the engine winds up and slams the u-joints and rear axle parts at every stop sign or traffic light. 1,500 to 2,000 stall speed should work right with that cam, and a stock converter wouldn't have any real difficulties.
Jerry

Jerry
Here is what I found out. I have two options, a stock converter that is 1600-2200 or 2200-2600. From your post I'll go with the stock.

Thanks
mac

Just got emailed a second option. A dirt track converter that has a stall speed of 1600-1800. Will this work better than the 1600-2200?

Mac

That converter would be an excellent idea. Here's why converter stall speed is important: Just before the transmission input shaft starts to move, a converter is capable of developing almost twice engine torque. For instance, if a crankshaft is developing 100 ft/lb. of torque ar a certain RPM, the converter is putting 200 ft/lb. to the transmission input shaft just as it begins to turn. As the transmission catches up to flywheel speed the torque boost goes away.

All converters have a "stall speed" where no matter how much power is applied, the locked-turbine crankshaft speed cannot increase without breaking something inside the converter. If that stall speed is below the engine's best breakaway torque, you get a sluggish launch. The fix involves modifying the diameter of the converter, or changing its internal clearances to allow the stall speed to increase into a better engine torque range.

Generally, the smaller the converter diameter, the higher the stall speed will be. Stock converters will be 13 to 15 inches in diameter and stall at 1200 to 1500 RPM, while a 3500 RPM drag race converter may be only 9 inches or so in diameter. If you can find one that stalls around 2,000 RPM or so, you can make more breakaway torque without sacrificing a smooth launch.
Jerry

Edit: Stall speeds are not exact. A "flash stall" happens when you hold the brake and nail the gas, and it will be slightly higher than a smooth acceleration from a stop. The converter with the narrower RPM range would be better for the street, if the cost is similar. I wouldn't spend a lot more money for a narrower RPM range, however.
Jerry