I have an 81 FB, with the A/c and air pump removed. I've been using a Gates 7320 belt. It's fine for a bit then it starts squealing @ 4000-6000 rpm range. Is there a better option for this application?

Thanks!

 

Are you running 1 belt or 2 belts, when the air pump is removed a 2nd belt needs to be added to help turn the water pump pulley, this means a dual belt pulley for the alt, also check the your FSM for proper belt tension.

 

I had the same problem even with 2 belts and solved the problem with some sanding and cleaning of the pulleys and proper belt tension (see thread).

https://www.rx7club.com/new-member-rx-7-technical-256/fb-screeching-belts-954202/

Get a duel pulley for alternator available from Mazdatrix for about $50 and two identical new belts. This should allow you to redline with no squealing belts.

 

Thanks!

 

You also could rock a gilmer pulley if you wanted to spend a bit.