Like the title says, anyone try a Mustang torque converter? My Roush has a 4R70W and I've got a stock converter from my old '99 Mustang with a 4R70W sitting here. The truck stalls at 1800 rpm right now, about the same as the Mustang did, but vehicle weight has an effect on stall speed so it makes an intriguing possibility for a basically free upgrade. Anybody here tried it or have an idea how much more stall speed you'll get from an additional ~1000lbs (guesstimate) of curb weight? The only thing needed for installation would be a Mustang flexplate as they have about a 1/2" smaller bolt pattern, outside diameter of the flexplate is the same.

 

I have a converter in my truck that stalls about 2800 and I like it. If you don't play in the mud then by all means get the flexplate and go for it. You will also have the benefit of reducing rotational mass by getting rid of that giant converter you have in there now.

 

Had a little brainfart earlier on the weight, probably ~2000 lbs difference or more. The converter stalled around 1800 in the Mustang with a 4.6, so add the weight and the torque of a 5.4 which also raises the stall speed, and it might just be a nice bargain increase...

 

I don't suggest putting the smaller diameter smaller clutch converter in a truck if you tow anything.
Alan

 

Good thought. I don't normally tow anything, but there may come a time when I need to. I could wire a switch to keep the converter from locking, but it would have to be a pretty short tow to do that. The Mustang converter clutch is pretty damn strong though, I had a slightly hopped up 5.4 in my '99 and made over 40 WOT dynojet pulls with the torque converter locked up and never had an issue with it, and it was putting down ~330-340 rwtq.

 

Everyone considers power as the largest variable on load but in fact weight is the largest issue.
Alan

 

Trust me, the converter needs to lock up when towing. The fluid temps will skkyrocket while unlocked, especially in OD. 3RD's not so bad. If the converter unlocks while in OD, shift out of OD.