All,

Please pardon me if this is a well-beaten topic but the transmission digits got me stumped.

With my 74 914 came a spare transmission that he said is a 901. Not so sure and I'm trying to make heads or tails of the numbers. I read earlier posts here that said the #s on the nose are a part number so look at the belly.

Belly says it's an HA 16 01 4

Nose says 914.301.302.00

Thanks in advance!

technically they are 914 transmissions

most of the inner guts are the same as the 901
so people mistakenly call them "901" transmissions

but the 901 is in a 911 and the ring gear is flipped over in a mid engine application... thus you have a 914 tranny

more importantly for value
is it a Side shift or Tail shift?

HA! funny. all 914s were a 901 box with different shift forks and tail cover and ring gear reversed like Brant said. (HA is the 914 transmission number prefix)

Thought so. Thank you very much!!!

I think I've heard them referred to colloquially as "901 Type 914"

Well it is a 914 transmission. The guts of the transmission, the shafts & gears are the same as used in the earlier 901, 902 and 911 transmissions and cn pretty much be used interchangeably. The differential is larger than used in most 901 & 902 transmissions.
Naturally, with casting #'s beginning with 914, the case is nearly unique to the 914.
So the 914 transmission is part of the 901, 902 & 911 family.

Your particular trans is from Jan 1974.

HA is not the only 914 type prefix Gussey
HB is known as well. It indicates factory ZF limited slip differential.