BRP "Hotside" Supercharger
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From: Camden, London
I know that I am jumping the gun here but does anyone know if this will fit a RHD car?
I am thinking of going CS but may wait for this if there is any chance (even if it takes a year or more!).
I am thinking of going CS but may wait for this if there is any chance (even if it takes a year or more!).
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From: Gie
To beat the horse a little more...
Positive displacement blowers like the BRP Roots/Magnussen derivative and the Lysholm screw-types always move a certain "extra" amount of air into the engine. "Extra" based on how much air the engine would pull under natural aspiration. Take out blower and engine efficiencies at different operating speeds, and the blower always moves X amount more air than the engine would otherwise pull in on its on. This equates to constant boost across the entire engine range for the idealized scenario above. Adding a positive displacement blower is akin to adding more cyclinders.
I think the term "spool" is more applicable to turbochargers and other free-spinning rotating machinery. The spool time of a PD or centrifugal blower is directly related to how fast the engine revs.
To clarify one of WLAURENT's statements: A centrifugal charger does not build boost in a perfectly linear fashion. The relationship between flow rate and blower speed is more of an exponential curve
Positive displacement blowers like the BRP Roots/Magnussen derivative and the Lysholm screw-types always move a certain "extra" amount of air into the engine. "Extra" based on how much air the engine would pull under natural aspiration. Take out blower and engine efficiencies at different operating speeds, and the blower always moves X amount more air than the engine would otherwise pull in on its on. This equates to constant boost across the entire engine range for the idealized scenario above. Adding a positive displacement blower is akin to adding more cyclinders.
I think the term "spool" is more applicable to turbochargers and other free-spinning rotating machinery. The spool time of a PD or centrifugal blower is directly related to how fast the engine revs.
To clarify one of WLAURENT's statements: A centrifugal charger does not build boost in a perfectly linear fashion. The relationship between flow rate and blower speed is more of an exponential curve
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From: Mesa
Originally Posted by wingnutLP,Sep 27 2006, 02:25 PM
I know that I am jumping the gun here but does anyone know if this will fit a RHD car?
I am thinking of going CS but may wait for this if there is any chance (even if it takes a year or more!).
I am thinking of going CS but may wait for this if there is any chance (even if it takes a year or more!).
Thanks for clarification SlimJim - was not speaking in literal terms, but it is better not to confuse anyone either. The point was that boost builds as RPM's increase and does not reach max until you are near the top of the RPM range.
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From: Sydney
As for the comparison between types of FI, regardless of the technical discrepancies and general differences the fact is the stated performance is far more akin to a mild off the shelf turbo simply because both has plenty of torque down low.
And if you'd read the beginning of this thread you would see that is the market it is aiming for.
And if you'd read the beginning of this thread you would see that is the market it is aiming for.
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From: Mesa
Originally Posted by AusS2000,Sep 27 2006, 03:22 PM
Of course it would be nice if the BRP actually became available before we run out of fossil fuels.
Or air for that matter 
I am still hoping for a 2006 install - but who knows.
