One of the limiting factors of tuning engines is ensuring that each cylinder is receiving the same amount of fuel and air as the next, with an AFR gauge only providing an average of all 4, in the case of the MX-5, it’s fairly common for the 4th cylinder to run leaner than the others, meaning we must compensate with more overall fuel, lowering how much power we can make.
One of the reasons for this is the intake design but additionally, the design of the stock fuel rail with the inlet and outlet on the same side will cause differences in pressure / flow across the rail.
What this radium fuel rail allows you to do is run a dual feed, or a single feed one side with a return on the other – ensuring the correct fuel flow across all 4 cylinders, it also has a larger bore and will take the added fuel pressure an upgraded adjustable fuel pressure regulator can provide.
This is for the NA 94-97 engines and comes with a fitting kit.
8AN ORB to 5/16″ Barb Fitting
8AN ORB to OEM FPR Fitting
8AN ORB Plug
Vapor Shield 5/16″ Fuel Hose
-Black Anodized Laser Etched Fuel Rail
-Stainless Steel Mounting Hardware
-Phenolic Thermal Insulating Washers