I need to know what the Mazda part number is for the rear counterbalance for 86-88 s4 engine. Also does anyone know the offset weight of this product from the factory... And the last question is, is Mazda the only company who makes or made this damn thing or are there aftermarket product available...... thanks

 

The 1986/1988 13B counter weight part number is 11-521A-N327 per the Mazdatrix site You can buy these counter weights from Mazdatrix, I will presume Mazda Motorsports & if you were to put an add in the parts wanted forum of this site most likely someone will have one for sale.

 

Sooooo, no then. Thanks...