Low-inertia supercharger

[QShip]

What is a low-inertia supercharger? I saw this mentioned on the MotorTrend website.

[Eswift]

everything that rotates around an axis has a moment of inertia about this axis.

moment of inertia is the sum of all the little bits of mass multiplied by their individual distances from the axis of rotation.

low moment of inertia is when weight is concentrated near the axis, and this promotes easier rotation.

high moment of inertia requires more energy to get it spinning, but it will like to stay at that speed once it has been attained.

spin around on your desk chair and hold some weights. bring your arms in, you spin faster.

stick your arms and weights out, you slow down.

low inertia supercharger operates on the same principle, it simply means a fast spooling, through a small diameter compressor.

I assume since we are talking about BMW, they are going to use some lightweight alloy, either for the screw or impeller, depending on if this is a positive displacement blower or not.

[QShip]

Thanks for the response!

Yes, BMW is talking about using it.

[s13sr20chris]

wow, bmw using forced induction? i never thought i would see the day.

[Eswift]

for the new M1....

well if you consider that the e39 M5 is NA and beats the pants off of anything mercedes can come up with, even a new redesign to directly compete with the M5!...

...so if bimmer went with forced induction, as mercedes already has, it will be supereme champion

[s13sr20chris]

remember the old m1? what a wierd car.

[Eswift]

why wierd?

i mean, if you are into the 80's supercar thing, and mechanical fuel injection supplying less than 15 mpg...

[s13sr20chris]

i think 80's supercars look cool but i dont care for mech fuel inj. im also kinda stuck on this notion of bmw being a "sport sedan" company.

[Eswift]

true, i think we all know the best BMW has come to a true supercar was in the guise of the Mclaren F1's powerplant.

BMW had a few really cool concept supercars after the M1, an italdesign concept called the Nazca.

[s13sr20chris]

im not familiar with that one. i have a book on the mclaren f1. it was written by ron dennis and gordon murray all about the car. from the get go untill present. it is absolutly fascinating.

edit: oops, not written by them. authorized by them and they were involved in the writing.

[Eswift]

http://www.geocities.com/Motor....html

and as far as I can tell, bmw ripped off nissan's mid4 concept, which was ripped off by honda, in the form of the nsx.

[s13sr20chris]

rearend has a very nsx kind of look to it. nice looking car. i would never have thought it was a bimmer. side note, (i dont care if we have completely hijacked the thread) i went to vir to watch the rolex sports car race and the bmw powered daytona prototypes had a nice sound to them. big nasty bmw v8 had quite a bark. i cant wait untill someone builds one with the vq. it has already been approved.

[Eswift]

very interesting....whats vir?

[maxnix]

Virginia International Raceway? Just a guess.

[s13sr20chris]

yup

also got a semi closeup of a nissan vq30 powered srpII car

[Eswift]

care to share?

[Mayhem_J30]

mmm...even better, wait for the M6 to return.

[Eswift]

who wants to take bets on what engine they will throw in there?

[s13sr20chris]

care to share?

yeah, i have to get my real close up scanned, but i have a couple taken with a digital cameral. let me attach them hither.

ok, never mind. i must email it to you if you want it. darn photo is too big. when i tried to resize it, the program i used saved it as some wierd file type.

if you want it, send me an email.[email protected]