belt/pulley question

What is the best choice of belt/pulley to use and why. 8mm,13.9mm etc? i have a bbc 540ci with a rcd idler and was going to run 8mm belt and pulleys on a bds 1471 but i am wondering if there is a better way to go?
Thanks

 

8mm GT, with Carbon belt seems to be working the best,

 

belts

8 MM seems to have the most choices for pulleys and overdrives. Also it is a lot lighter than a 14 MM belt. Plus price. Don

 

8mm gt

There is nothing wrong with the 8mm setup, the really good poly chain or carbon GT belts are still fair priced, we bought two of them but have been using the same one for two years and its still looking new.

 

I run 8mm stuff on my BBC on have had zero problems. I run used 8mm/1600/75 belts that I buy off a local TAFC/TAD racer that puts a new one on every 5 passes. I have a bunch if you need one. I would imagine your spacing is similar so I could give you the info on what pulleys I run also

 

All of what has been said is true. But, if you don't care about a little extra weight, little more cost and can use the belt and pulley combinations, the 14MM GT stuff is bullet-proof, especially on freshly stripped blowers. Use the PS series belt and tighten it correctly and it will last. The last belt I had in 14MM has 75 runs on it and never had an issue turning it 53% over at 9,000 RPM. I snapped and stretched a few 8MM belts and that is why I went to 14MM for a piece of mind. Didn't run the carbon though. Anyhow, it worked for me.

 

i was wondering the same. going to be at 10-25% over on a 12-71