The majority of cars on this forum run Gatorbacks, and I have yet to hear of one slipping on this forum, so why is this an issue?

Wow this topic went into left field. And all I wanted to figure out was whether I should go to an oversized tensioner or a smaller belt.

The prior owner of the car ran a smaller pulley with the belts currently on the car without a problem. I will wait to see what a few weeks with the smaller pulley I'm going to put on later this month does to the belts before I do anything.

Thank you everyone for sharing your experiences.

Mortehl, buy the oversized tensioner pulley now. Plastic, not metal.

Issue? Read the past posts... I know of at least 3, one of them being me. You don't seem to see what I am saying. I never said that a Gatorback will cause belt slip, actually they are a great long lasting belt. All I said is that if you have done everything else - smaller belt, larger tensioner and still have belt slip get a Gates. Or if you want the best grip possible get a Gates. I run a smaller tensioner, smaller belt, a 2" pulley, and a Gates belt and don't have a problem with belt slip. Try doing that with a Gatorback and see how many and how quickly you will go through belts. Believe me I've gone the Gatorback way and have gove through 3+ belts in a matter of days. Testing that is backed up by my personal exp...

As far as Mortehl'* ?, I would get the larger tensioner and while you have the belt off check the condition of the belt and the length of the belt to see if it has streched. Oh by the way you can get the larger tensioner at NAPA cheaper then online and while your their you can pick up a Gates belt.

You guys are persistant. I'm going to have the belts off this weekend and I'll look and see how the smaller pulley treated it while I'm there. I appreciate the input delivered by all.

I've been running an oversized tensioner for two weeks now, and running the stock belt, I had issues with belt slip. I tried the Gates belt, and after one week of running it, the darn thing is almost gone. The ribs on the bottom of the belt are almost flat from where it rubs together over top of the tensioner. I'm thinking I need to go back to the stock tensioner pulley, and go with a smaller belt.

The Series 2 belt routing and wrap diameter is a totally different animal. However, we have many here running smaller pulleys on the S2, so I'd go with what they do.

I agree 100%. The gatorback is a good belt, but they do slip easier than a gates belt. My dad used to run a gatorback on his GTP until he got down to a 2.7" pulley IIRC, then it started to slip. He went to a gates and did not have any more slip. After about 10k miles with a gates belt he started to have a problem with it slipping but it had 10k on it and he had dropped 2 pulley sizes (from 2.7" to 2.55"), so he converted it to 8 rib since he had to get a new belt anyways. Now the tensioner doesn't have to be nearly as tight and there are absolutely no signs of belt slip now.

To answer the original question, I would go to an oversized tensioner before a smaller belt since it increases the belt wrap around the supercharger pulley. Then go to a smaller belt after that. But from what I've read, this is pretty much the answer you've gotten from the other replies.

Shawn