Ok just wanted to see if anyone has noticed the same. I have been around FI cars all my life many twin screw cars, eaton cars, centri cars, turbo cars etc etc. I have a fondness for Gates belts nothing seems to last as long or grip as well. But since they do not make a 7 groove in the size I need for my XJR6 I am forced to use the jag belt. Which sucks beyond suckiness lol. I mean heres why I say that, the belt has ZERO grip no matter how tight you make the belt. If you try and turn the blower you can still slip the pulley meaning the belt is too slick. Second it wears out even when tightened to factory specs I have literally gone through 14 belts in less than a year and lucky the jag guys keep warrenteeing them for me, nice guys. I replaced all pulleys after the 3rd belt thinking that was the prob, NOPE, even got the micrometers out to check alignment and they are dead on. The belts just are not made to strong standards I mean the later 99 xjr blower belt is nice why cant they use the same belt material?? I can get a nice poly grip belt from autozone thats not made for blower duty 6 groove and not only does it last longer but it grips like noones buisness I tighten it to factory specs and then try and turn the blower and it will not turn without turning the whole motor over, meaning zero slippage.

Anyone with belt slippage problems may want to look into their belt before thinking its too loose, I can tell you first hand my car is quite a bit noiceably faster with the 6 groove 15 dollar belt versus the factory 7 groove 50 dollar belt and on top of that its been my back up belt for the last year and has never failed and looks as new as it did when I bought it wish I could say the same about the jag belt

 

I assume you've been to a well-stocked parts store and asked for a Gates belt by dimensions and ribbing? I prefer Gatorback belts and have matched belts by dimension/ribbing, rather than by application (but not for the Jag).

 

I love the gatorbacks and if I could find a place nearby that still carries them id get one of them I think they are a great belt

 

I would say either you got all the belts from one defective lot, or you have another problem. 14 belts? Somethings wrong!

 

It would have to be batch cause the supercharger is new, idler, tensioner and crank pulleys all brand new, and after I measured them they are all lined up dead on. So next I would suspect installer error but I use the factory tool to measure delfection and have tightened it right too that, under tht, and over that and nothing helps it either slips or it starts to fall apart. I dont know cause like I said I have had a 6 rib autozone belt on it for monthes without fail and its a piece of crap. No slipping, no falling apart, no nothing.