Supercharger
The new MPS/G 250 record is 131mph (210 km/hr) which rules me out as I cannot get tyres rated that fast (assuming that I could get the scoot going that fast). Time to change class to "B" for blown. I did have a IHI RHB31 Turbo Charger Rotrex a lot
Using info from Supercharged! Design, Testing and Installation of Supercharger Systems Rotrex Technical Datasheet C8 Range.pdf Rotrex Technical Datasheet C15 Range.pdf Rotrex Technical Handbook.pdf
These are calculations in progress - I started looking at the C8 but the C15 might be better...
Rotrex C8/15 Vs ProCharger A-1
Summary from just looking at specs online - the A-1 looks cheaper and probably(?) less efficient but may be easier to fit and would have less stress on the engine. The A-1 however is twice the size of the C8, which might make the C8 better as weight can be distributed (e.g. oil reseviors etc).
Stats
ProCharger winning but unsure if we are comparing apples with apples...
* ProCharger provide less info than Rotrex - I suspect that A-1 is a group of superchargers like the "C8". Rotrex provide info for each model (e.g. C8-6, C8-8, etc) but it looks like ProCharger just give info in a range and pick the best value.
Size
Rotrex is much
Using a 1/1 model we see that the Rotrex is the only choice based on size.
Extras
ProCharger requires:
intercooler
Rotrex requires:
intercooler (probably a better one as it would generate more heat)
oil pipelines and configuration (some of it supplied)
Calculations
From Rotrex Info
C8-8 looks the best choice based on Rotrex Technical Handbook.pdf
Flow Rate
The rule of thumb for flow is:
So for 50Hp we need: 0.042 kg/s
Pressure Ratio
The rule of thumb for pressure ratio is:
So for 50Hp from 40Hp we need: 1.44
From Bell Book
Comparing Bell to Rotrex
Flow Rate
Bell states for a 4 stroke:
Airflow rate = (cid x rpm x 0.5 x Ev)/ 1,728
So for a metric two stroke:
1 cubic centimetre = 0.0610237441 cubic inches
Pressure Ratio
The compressor map below shows that the C8-8 will give this at 160K-200K rpm (~13K-~17K input rpm) - though I need to understand pressure maps more (off to do some reading).
