I test fitted them before I put my wheels on and they looked the same fit as the rays valve stems. I'm not sure what you mean by the rubber washers stretching because tightening them down flattens and stretches them anyway. It was the same for the rays. Fitment with the TPMS should be fine. 
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SOLD 12/30/2011 2010 370Z Coupe Monterey Blue 6MT/Touring/Sport/Nav
F.I. CBE CF w/ 12" Res | V1 | SecondSkin | Stillen G3 | EVO-R CF B-Pillars | Volk GT-S Ti Gunmetal 19x9.5 +30 F, 19x10.5 +8 R | Swift Spec-R Springs
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