My main problem is that I have yet to find anything that's specifically for the FE3N. It's all measurements and see what's available for other cars. I ordered the +1 Miata BP05 valves from fab9. I'll check all measurements when they arrive before ordering springs. I measured an installed height of 33mm(ish) BP05s look like they have between a 34mm-35mm depending on source. Again looking at supertech catalog for single springs and I'm seeing the BP, RB20, Honda B18A/B, B20, RB25, VG35DET, 1JZ,2JZ, MZR 2.0,2.3,2.5, and Turbo, duratec 2.3,2.5 all have the same valve springs with an installed height between 33-35mm. Which are close enough in specs to fit the FE3N. According to my measurements The valves and springs are within the total range of the cam's 10.7mm lift. The valves are 1.4mm shorter but the Miata single springs are good for 12.9mm max lift.