Rebuilding my A500, considering upgrading the torque converter to a Viper series from PATC.

Can you guys recommend an ideal stall speed for the stock 3.9 (non-Magnum) motor? 2WD, '89 Dakota. Nothing fancy. The truck is strictly for the street.

At what RPM does the 3.9 produce optimum power?

The TC I'm looking at comes in stall speeds from 1800-2800, I'm thinking 2400 but all the stuff I read is rather confusing since I don't know what the 3.9 looks like as far as it's power curve.

Thanks!
Ivan

 

I probably would not go any higher than 2000-2200 and that might be pushing it on a stock engine. It should probably reach its max torque at around 3000RPM and peak HP at around 4000RPM. Maybe you can elaborate on why you think you need a higher than stock stall speed TC. If you are keeping the engine stock, I think a shift kit would be a much more worth while investment. I guess it also depends on the price of stock vs. "performance" TC's. But I can't see anything higher than 2000 being worth it in that truck. Just my $.02

 

Sorry I should have mentioned, putting a Transgo TFOD-HD2 in. Aiming to program it for hard but not tire-chirping shifts.

I was thinking that a higher stall speed would give me a faster "launch" off the line, I would also like to be able to break the tires loose without using the brakes if that is even feasible with this engine and truck.

The aftermarket TC that I'm considering is a Viper series from transmissioncenter.net for $315. A stock replacement from Autozone would run about $100.

Thanks for the input!

Ivan