13.9mm belts?

Hey any of you guy had any luck running the 13.9mm belts in the small width of 65mm instead of the wider 75mm ones? How many runs before losing them. I already have the pulleys I need to run this combination and hate to buy all new ones. Let me know what your thoughts are on the 13.9mm stuff. I've even heard you can use a 14mm on 13.9 pulleys? I'm sure you all have tried them before going on to 8mm, 14mm, GT stuff, or even 11mm now. Don't let someone win with a new mm belt next week, or we all will be running it next uh?

 

We were told (and now use) our old 13.9mm pulleys with the 14mm belts with our roots style TAFC. The belts we use are a little over 3" wide I believe. We have had no problems with that, however we were also told that you can ONLY do this if it is a 14mm GT2 belt. We actually like it better than running a 13.9mm belt on 13.9mm pulleys because the tooth profile is slightly different and I guess, in theory, it would be less likely to trap air under the teeth, which would throw the belt. Thats just our thinking. Anyways, the 14mm GT2 belts DO work on 13.9mm pulleys.

 

the narrower belt will work fine in most blown alch. applications. it's almost impossible to know how many runs you can get on your blower belts there are so many variables. tire spin,fuel system malfunction,to much clutch to little clutch. as far as the pulleys i agree with what nathan said. i probaly get asked once a week can i run 13.9 on 14 pulleys. many manufactures don't mark there pulleys. my thought on it is if you can wrap the belt in the pulleys run it. there is .004 difference between centers on the teeth and there is .014 difference in height on htd 14 belts over the 13.9 the gt has same height as 13.9 and the .004 difference between centers. at 12,500 plus rpm on the blower and 8,500 on the crank i don't think the belt will know the .004 difference good luck with your hot rod and if you need any belts give us a call thanks jr rbssuperchargers.com 530-292-3040