The A cam is a significant upgrade to the M cam regardless of which transmission you are running. My response is typically geared towards someone who is inquiring about running a K cam in a car with an automatic transmission. There is certainly nothing wrong with running an A cam with a manual transmission. You won't notice a lot of bottom end loss and it will pull hard right to red line.

I seem to type this paragraph about as often as the "sorry, I have no K cams at the moment" line...

Don't forget, both the K cam and the A cam were stock cams. They are not "performance" cams. They do perform better than the M cam in a B230F. The A cam came stock in a B21A, an engine with lower compression and smaller displacement than the B230F, and did just fine in both manual and automatic versions. It will be fine in a B230F, auto or manual. The K cam came in the B23E which is the same displacement and only slightly higher compression than the B230F. It also came in both auto and manual versions and did just fine in both. The only reason I don't recommend it in an auto car is that someone who now has an M cam will notice some bottom end loss with a K cam and the K makes power where people who drive automatic cars don't typically drive; in the 3500-6000 rpm range.

The K likes to be revved regularly. Failure to do so will result in much accumulation of deposits in the intake runners due to the reversion it creates at low rpms. I can't tell you how many times I've pulled 405 heads (the B23E had a 405 head and K cam) and found the intake ports almost closed up because the soccer mom or grandma (or both) who had been driving it for the last 20 years never revved it over 2500 rpm...

Bottom line is they will both work. The K is a better choice if you drive with your toe pinned to the floorboard on a regular basis...

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Dale