Power output of DB601 + 100 octane

[Seadog]

Originally Posted by 41Sqn_Banks

As can be seen here the power of the Merlin III +12 boost at sea level is about 1190bhp (= 1207 PS) and increases to 1310bhp (= 1328 PS) at 8800 feet.
The highest power of the DB601N is given as 1260 PS.

At 5km (= 16,404feet the DB601N again has again 1175 PS, compared to the 1025bhp (=1039 PS) of the Merlin III.

At 7,62km (= 25,000 feet) the DB601N still has 850 PS (= 838bhp) compared to the 750bhp (= 760 PS) of the Merlin III.

So basically the Merlin III has slightly higher power at low and moderate altitudes (32 to 68bhp), however the DB601N has much more power at high altitudes (~90PS).

I'm wondering why the manifold pressure of the DB601N is 1.35ata, I had expected something like 1.4-1.45.

Thanks.

Of course the Merlin XII and then 45 would have shown improved high altitude performance.