Price
There`s no point in building a strong bottom end and not using the best fasteners! We worked with ARP to design a main cap stud specifically for a Miata instead of using something else that was close but not quite right.
If you use a Main Bearing Support Plate (MBSP) as found on 2001-05 engines, you will need to do a bit of clearancing to make room for the studs.
Includes studs, nuts and lubricant. Fits NA and NB Miata engines.