Sure-Grip or Not

I had a Auburn Gear cone type professionally installed in my Dodge Ram. It lasted about a year. The springs in it broke. I was like WTF!
I went back to open carrier.
Been looking at Detriot Trutrac locker now because I will be installing a 408 pretty soon.
Just me thinking... if I have high performance engine and only one tire is getting traction... why do I even need a high performance engine??
If u have reall hi h.p., don`t waste ur $ on that tru trac, I had one in a vega /approx. 600 horse/14x32`s, and it wouldn`t hold. Sold it to an offroader for $50. I went to a Detroit locker, and have used one in every car since.