My 1st attempt at a big block. Engine is stamped DJ190. 420??? Mild port work,billet rod/flywheel and worked carb. Ordered a cam that said it was for 390/420 but it's sloppy in the block. Cam bosses are a little larger than the 390s. Browsed around but most big block stuff says 390/420. What engine do I order for that has the bigger cam bosses? Thanks in advance.
