Hey guys, it's been quite some time since I've posted but I've had this problem for years now and since I'm driving the Talon a lot more now I figured I'd get down to solving this problem. Whenever I take the car up to very high RPM usually in 1st or 2nd. I'm talking near redline and at full 9PSI of boost. I will throw my PS belt. This belt is tensioned by the PS itself as I've removed the AC and I'm still running my OEM crank pully. It's the shorter belt which is K050405 or 5050405 depending on manufacturer. I've made sure everything is aligned right and it's almost always a belt that is only a few months old at the most. I've been having this problem for years now and I'm getting tired of buying new belts (I should put a big thing of tie wire around the belt to catch it when it throws it off the car, haha) so I figured maybe you guys have had some solutions. Every once and a while I'll get lucky and notice it right away and the belt will still be hanging out on the crank pulley if that helps for solutions at all. I have an underdrive pulley laying around I could throw on if you think it might help. :shrug:

Get a Goodyear Gatorback belt, that solved my belt issues. I was having the same problem. Also double check the tension on it.

If its a 420a motor there is black round solid metal cylinder (like a bump stop) with a 2 bolt flange that mounts to the right motor mount near the strut tower. I had the same problem. When i looked at my mount all that was left were pieces of the broken flange under the mounting bolts.

i had this issue also, turns out the crankshaft pulley wasnt pushed in all the way so it was slightly out of align. It might look like its aligned by eye but it was off by a hair so at high rpm's it would come off. i lost so many ps belts i was going to get rid of the ps all together. i just used an impact gun on the crank pulley(even though thats frowned upon) to tighten it down more.
Also maybe the pulley the belt rides on is bent.