twin turbo 360 rpm limit?

No reason to spin over 5500 with a turbo.

First you need a target horsepower number. Then you calculate the mass flow.

Let's say you want 600 horsepower. To get there you will need 57 lbs of air per minute stuffed in to that 360 @ 5500 rpm

VE calcs say about 12.6 psi boost should get you there. That gives a pressure ratio of 1.86

Map for the Hx35:


So divide the mass flow by 2 for twin turbos, and you get 28.5 lbs/min flow. The intersection of 1.86 & 28.5 is no where near the choke line.

Let's say you want to get stupid, and go for 2.5 hp / cid - 900 hp @ 5500 rpm:

86 lbs / min flow /2= 43 lbs/min 27psi boost = 2.83 pressure ratio

Nope, still not choking, and actually still near the 72% line.

Ok, how about 900 horsepower @ 4500 rpm? Still need 86 lbs of air, so the boost goes up to 35psi. Pressure ratio of 3.4

Nope, no choke even there. Still on the map.

But you wanted high rpms. So 900 hp @ 8,000 rpm 14 psi boost. 1.9 pressure ratio. Still 86 lbs/min NOW you are getting close to the choke line.

Bottom line is keep the rpms lower. Spin to 4500 & ask for 500 horsepower. 13 psi of boost & 47 lbs/min flow. It will live a long time.

B.