A. I'm not convinced that there were no B30E engines produced in

1972. You can measure the head thickness to determine for sure.

The E head is about 3 3/8" thick (slightly less) and the F head

is about 1/16" thicker, about 3.425 so if you are good with a ruler

you can tell them apart.

B. Most parts on the 74 were still interchangeable except the crank,

rods and pistons. In fact the main bearings were the same so you could

put a 6-bolt crank with rods and pistons into an 8-bolt block.

I am not sure about the B30 but on the B20 the maincap bolts and the

bellhousing bolts were both changed to M12 1.75 but everything else

was still Unified threads as before up to the end of production.

C. To the best of my memory the few 75 B30s I have seen did not have

electronic ignition. The 75 B20s DID have electronic ignition.

The engine was still called the B30F. The cam was changed to what

some call a "smog cam" somewhere along the line. It was somewhat more

radical than the "C" cam used in previous B30s, both FI and carb.

D. Only the ones with fuel injection. The carbureted models were

just called "164".

E. 164s have NOT vanished! I drove one less than an hour ago.

I've had it over 30 years and it is 32 years old, 279K miles.

Got the IPD street perf cam and even with carbs does WELL

(er, ah, till you get to the gas station).