In certain US Markets EFI B230's couldn't pass emissions with the A cam, nor with the more aggressive K cam. The base idle is rough, lopey, and uneven on both cams, as is engine vacuum, so an engine that has the ability to adjust base idle and timing performs better with them.

The cam of choice for the EFI engines is the VX3 or V cam which has much narrower lobes and has higher vacuum at idle than the A or K cams. This makes the VX and V cams idle more smoothly, not just pass emissions more easily.

Although these cars (and cams) are older and the emissions are relaxed a bit since the 80's and the A & K cams can pass emissions, the Vxx cams do perform more evenly throughout the rpm range than any of the other early cams. IPD once sold the A cam and stopped selling it for this reason. I personally scrapped the A cam due to poor idle and studder due to low engine vacuum in both an LH 2.4 & 3.1 240 and put a VX3 cam in instead and am much happier.