Well, what Bob failed to mention was the circumstances under which they occured. Read the posts and you'll see what they were and what comments I've made. If the low risk is acceptible? Well, thats up to you.
I've run UD pullies on three different cars now. and having put a little over 30k on them with the ranger, for a 4.0L it's a very solid bang for the buck. Low rpm tip in throttle response is noticable as is power while accelerating.
Shoot... I pulled a 3500lb boat 1200 miles through the mountians, had the bed loaded down, 4 adults on board, and it was fine except for the emergency stop at the top of the mountian. And even then it took a few minutes to get too hot. Read my posts and you'll see what that extreme experience was all about.
Oh and btw.. my power figures are considered to be "at the crank". They are as measured / calulated by the trucks PCM. Not measured at the rear tires on a chassie dyno. Rule of thumb there is 20%. Meaning 12hp at the crank would measure 9.6 at the rear tires. And also something else to consider.. I removed the stock fan at the same time I did the pulley swap. How much power was gained from each I don't know. I *suspect* the bulk of it came from the pulley.
It was cold out side and the stock fan freewheels for the most part under those conditions.
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