I think the 901 is the way to go for towing. With the steep gears you have the 941 would probably work well too but gas mileage will be a tad worse. I could see a 50HP gain from the stock cam with the 941 but that's kind of a stetch. The newer grinds are much improved over the old.

 

What about this Crane cam for towing? 443904?

http://www.cranecams.com/truck/443904.htm

 

That is for a 351W. Try this one.

http://www.cranecams.com/truck/343904.htm

 

So which one is better for towing?

343904 or the 343901 ???

 

They are the same cam. The 343904 is a kit of some type with the 343901 cam included.