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Valve spring kit

Valve spring kit
Valve spring kit
A well-designed valve spring upgrade - with titanium retainers. Ooooo.

Availability: In stock



Carefully specified for the Miata, these springs are part of the ideal NA/NB Miata head. The titanium retainer's light weight means there's less reciprocating mass. The well-matched spring rate means your valves are better controlled at high engine speed but without the drag and extra stress of a too-stiff spring. In turbo cars, the exhaust valves will seat better even under high backpressure. As an added bonus, they also allow for greater lift (12mm or 0.472") if you're running different cams. They are designed to allow engine speeds of up to 9000 rpm before valve float - but if you're planning on doing that repeatedly, we do recommend using our dual springs instead.

Aluminum spring seat, chrome silicon steel spring and titanium retainer. Sold in sets of 16 for a complete head. Fits all NA and NB Miatas. NA valves will require the use of valve keepers from a NB engine (not included).

  Head Diam Pressure (lbs@mm) Max lift Coil Bind Rate
  O.D. (mm) I.D. (mm) Seat Open (lift) mm mm lbs./mm
1990-93 27.50 20.00 58 @ 34.10 157 @ 10.5 11.90 20.70 9.40
1994-05 27.50 20.00 56 @ 34.2 154 @ 10.5 12.00 20.70 9.40
Additional Information

Additional Information

Part number M04-66600
TÜV approval available No
Fits: 1990, 1991, 1992, 1993, 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

Customer Reviews 1 item(s)

Great upgrade for NB2 VVT engine
Purchased this kit for my NB2 VVT engine that I was rebuilding. Wanted to make sure there was no valve float at high RPM due to the aggressive ramp angle of the VVT intake cam. Seems to have done the trick! I'm making power all the way to redline!
Review by Peter / (Posted on 5/20/2016)
Instructions for this part are not currently available online.