We have had zero luck with non-roller lifter cams....Even ones that worked for years are now failing. I suspect they changed the oils and there is not enough zinc, even though they say there is...Been lied to before.....

'70 Cuda,...605 EFI Hemi Street Car (6.20 best pass, 1.33 60ft)
https://www.youtube.com/watch?v=WYw6RA-k5Bk (6.25 at 108.75mph from inside car)
https://www.youtube.com/watch?v=3zQEb9uxFng (6.25 at 108mph from outside car)
https://www.youtube.com/watch?v=JCvfzsC4NgM (9.9)

'66 Barracuda AWB Stretched nose Blown 440 Car in build stage

'71 Duster Drag Car 400 Low Deck 512 best 6.002 at 115.44mph
https://www.youtube.com/watch?v=Znuo3jMUXTk