My Yellow Cap group 24 AMG style was doing slow crank but is 7 years old but my engine is a 512 with 10.5 compression.
This 7 year old Resto. AMG would still work fine if my engine was stock with less timing.
I opened the bottom and ordered the biggest most powerful battery to put in it but cranked slowly still.
I returned that and then bought a Group 24 most powerful Duralast Battery and a Yellow cap topper and
that cranked great cold but slowly when hot. I returned that yesterday and bought the most powerful group 27 Duralast and problem solved.
I have a group 24 yellow cap topper if anyone needs one!!
Ron