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Inconel 1mm oversize exhaust valve (1.8)

Inconel 1mm oversize exhaust valve (1.8)
Inconel 1mm oversize exhaust valve (1.8)
Oversize exhaust valves for more flow - now available in Inconel!

Availability: In stock



Oversize exhaust valves will flow better and make more power. Our valves are heavily backcut to give more airflow at a given lift and 1mm oversize for more flow. Plus, we have Inconel!

If you`re going pushing for a specific output of more than 130 hp/liter (basically, anything more than a standard FM II), it`s recommended that you change to an Inconel valve. The exotic 751 alloy can handle much higher heat than stainless steel. It`s a lot more difficult to machine and heat treat so they cost more, but it`s well worth it. Inconel valves are only available in the 1994-05 exhaust size.

Price is for one valve. You will need 8 exhaust valves for a Miata engine. 1.8 valves are made with slightly longer stems than stock to allow for more precise installation with solid lifters.

Additional Information

Additional Information

Part number M04-66555 BP INCONEL
TÜV approval available No
Fits: 1994, 1995, 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004 (non-MSM), 2005 (non-MSM), MSM
Manufacturer No
Flyin' Miata exclusive No
Fits Exocet? No
Proposition 65 Warning: Cancer and reproductive harm
California emissions No information at this time
Instructions for this part are not currently available online.