Diabolical!

If he's already got a thump and is still shredding belts, then no aftermarket tensioner will fix the problem. Alignment of at least one of his pulleys is definitely off.

This should give you an idea of how to attack the issue: http://www.mapro.skf.com/products/AL_intro2.htm

flounderlipps

Here is a link to a DIY 8 Rib kit
https://mustangforums.com/forum/4-6l...onversion.html

I would also suggest like others have to check your pulley alignment.
the UPR tensioner works very well, the Steeda looks like you need a 1/4" extension on your breaker bar.There is not much room for a 1/4" extension between your tensioner and your radiator.
http://www.uprproducts.com/mustang-b...ioner-arm.html

Get a 1/2" extendable ratchet from Harbor Freight and keep it in your trunk
http://www.harborfreight.com/hand-to...het-98831.html

908ssp

The thumper is garbage. It is designed wrong so it is no wonder it doesn't help. The throw is too short it has no more pressure than the stock and when it hits the stops the shock loads are out of this world. The DOB addresses all those issues.

Diabolical!

Lol, designed a competitor? Tell me, what's the failure rate on the thump? I'm not gonna bash the two-stock-tensioners setup because I've never personally used it, but the thump works fine for everyone who uses it.

flounderlipps

I use a Thumper tensioner and it works very well, never a problem.They are pricey tho.There are other tensioners out there that will do the job for a little less money.