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      11-10-2012, 11:48 AM   #21
Andrew@ActiveAutowerke
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Drives: 2014 435I M-sport
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Quote:
Originally Posted by LarThaL View Post
So what led you to Rotrex. From what I have heard, they aren't the most reliable of units.

HKS 8555 is rated at 918 CFM
Rotrex C38 91/92 is rated at 1205 CFM
Vortech V3si is rated to 1150 CFM

Don't quote me 100% on those conversions, both manufacturers use some odd-ball flow rates instead of something standard like kg/hr, CFM, or lbs/hr.

The rotrex 92 offers a larger housing, think S-cover in the turbo world. The wheel is not setup any differently but the cover breathes better.

Now the comparison with the Vortech. There are alot of other factors not taken in to account here. These are peak flow numbers but do nothing to reveal how the blower acts in anything other than 100% speed. The wheel geometry can change the dynamics through the blower rev range quite a bit. It is noticeable that the Rotrex/HKS units offer more flow at lower revs than the Vortech, which tends to be a bit peaky. Blowers can be under/over spun etc.
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