Picked up my finished Mast heads yesterday. FWIW, just have Mast do this if you decide to do these heads. The valves (Manley severe duty stainless on intake and inconel on exhaust) are longer than stock due to the increased deck thickness. Also, the spring locators and valve locks are not the same as stock LT1. So I ended up buying all that stuff from Mast anyway. The dual valve springs and titanium retainers came from CamMotion. Now just going on week #8 waiting for my pistons & rods from GPI...
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2017 Chevy Camaro 2SS A8 Whipple 3.0, Mast Black Label heads, Fore triple in-tank pumps, 112mm TB, LPE +52% injectors, LPE BB HPFP, 15” conversion 1059 WHP/944 WTQ, 9.48@150