I just installed the RBeat dual alternator pulley and I'm looking for the proper width and angle belt. All the parts shops keep showing me a 7/16" (0.43") 40 degree belt. This belt sits too high in the pulleys and I suspect that the proper belt angle should be 30 degrees. I have an old original belt (Gates) (mazda part number 8311-18381A9U). It is 3/8" (0.375") and appears to be at 30 degrees (V designation). It sits much lower in the groove than the other belt and generally seems like it fits better. Does anyone know more details on the correct belt specifications for my '88 NT and what aftermarket belt would be best. I've been frying belts at 'track day' and I believe it's because I've been buying the wrong spec belts..

Thanks.

Babbs

 

um you could just go buy a couple more 8311-18-381's at the dealership....

 

Last time I did that they gave me some Korean made brand that was 7/16" wide. I'm planning on talking to the dealer again to see if they can locate belts with actual part numbers on them, like my old one. The Korean one only had generic numbers on it but it was in Mazda packaging.

Babbs

 

Just for your information.

I ordered the OEM belts (mazda part number 8311-18381A9U) and Mazda gave me the correct one. Part number printed right on belt. Fits much better than any aftermarket belt that I could find.

With dual belts on the alternator/water pump, I should be ready for some fun track days.

Babbs.