Miata Alternate Head
#38083 from Donald Tucker · Not recommended · Minutes (2025-05 Fastrack)
Thank you for your letter but this is not recommended. Permitting the '99+ head would create an engine & chassis combo that
never existed from the factory. Additionally, the advantage this classification has is being permitted a full-prep chassis
allowance, which the '99 Miata in EP does not have. This explains why they have the same weights, where one has a full-prep
chassis, and the other is capable of slightly more power. Lastly, although sourcing pre-99 1.8L Miata heads might be more
difficult than finding '99+ 1.8L Miata heads, it is by no means impossible, especially when compared to what many other
Production racers go through to source desired and usable OEM parts for their cars.