Im doing a 5.4l swap for my truck and i have come to a fork in the road... I dont know where to install the 4.6l torque converter or the 5.4l torque converter... the 4.6l has a higher stall speed than the 5.4l.. but im not sure what it is.

Anybody have any opinions or ideas?

Thanks

 

Well, I am not so sure the 4r70 will handle the 5.4 so well, you might as well reuse your 4.6l converter. Upgrade the converter when you have to upgrade the trans, for the 4r100 factory tech includes a new t/c, they may for the 4r70 as well.

 

WOW reAX you have a sweeet mod list..I tought most of the 5.4L had 4R70 trannys..???

 

The 150s might. But I have a F250 and I am sure the lightnings have 4r100s as well.

 

99% of the F150's use the 4R70W. It is a tough tranny and with normal maintenance, it will last a long time behind a 5.4L.

 

There you go, as long as you keep up with it and stay n/a your stock might just last you. Your trans may not handle a s/c though.

 

Im not worried about the tranny.... ive been through one already and i was so brutal to it and the only thing that offed it was a dang bearing... and i even drove the truck 150 miles home to put the new tranny in it.... Now thats tough in my book...

But back to the torque converter question...any opinions... i dont know if the 5.4l will benifit much from having a higher stall or not.

 

They hold up well in 9 sec Mustangs too.

 

nobody said anything about a super charger....and i was told by somebody on here that the 4r70w with a few mods will take 600 HP.. with out a problem...

Dont Knock something you havent tried...

 

I would think the 4.6l had a slightly higher stall rating, making the motor turn faster before appling power to the trans. I wouldn't think it would make a huge difference in your set up. I certainly wouldn't spend money on a stock one, even though aftermarkets are rather expensive.

If I do a t/c before my trans goes, I will get either a precision industries Stallion or Factory Tech dominator. Either seem to be money well spent because of the higher multiplier along with the higher stall speed.

 

I have acess to both... all i want is some opinions on which torque converter to go with... the 4.6l that does stall higher... or the 5.4l that will hook up a bit earlyer.... it would tow better with the 5.4l converter but leave harder with the 4.6l converter i suspect. any objections to this thought process.

 

Well, the 4R100 in a SD with a 5.4L stalls higher than the F150 with a 5.4L. I'm thinking the higher stall speed would get you into the torque band of the engine faster and be a benefit all of the way around. I'd try the 4.6 converter. I wish my 5.4L stalled a bit higher when towing, myself.

 

Ya, I like your thinkin LXMan. I wonder why Ford made it stall lower on the 150's

 

Very simple.Better fuel economy. In most cases,the average user will get better fuel economy with a lower stalling torque converter.
In your case-I'd use the converter with the fewest miles-the clutch in the OEM torque converter is weak on both versions,so you'd be better off with the fresher of the two.
And the 4R70W will handle alot of power reliably.
JL

 

If you're looking at the 245mm or 9" PI converters-avoid the single disc lockup clutch model.I've seen many of them trashed by stock cars-they're simply put...garbage.
JL