What is a 408???
WARNING!!!!!
Sonic check any 318, Poly engine before attempting to go north of 400 cubes. Not every 318 or POLY 318 cam take a .090 overbore for that magic 4.00 bore size.
Also a side note .... there are larger stroke cranks available if you NEED to have more than what the 4.00 arm delivers. They will fit in a POLY engine just as fine as a LA.
