DB 601N and DB 601P

[j harris]

What are the principal differences between the two engines please?

 

[Denniss]

Different prop/gear ratio, at the same engine revs the P spins the prop at lower rpm.
-> 1:1.88 instead of 1:1.55 in the N

The same ratio in A/B and Aa/Ba, similar ratio changes from 601E to F/G or from 605A to 605B.