This is actually on my '03 Eaton-blown Range Rover... sorry, but there aren't a lot of supercharged Rover forums, and this is sort of a general blower question :-)

Looking at the way they've set it up, the bypass valve dumps to the atmosphere. On LT1 cars, the Vortech setup dumps the bypass air back into the intake stream post-MAF, whcih makes a lot more sense.

It would seem to me that on this Rover setup, air dumped by the bypass valve has already been metered by the MAF, so I would think the PCM would be totally confused about the mass of air when the bypass valve opens.

Has anyone seen another setup like this, and any speculation on how it can work?

- Dave

 

I guess it depends if the MAF is pulling or pushing (pre blower or after blower).

If it's pulling, it shouldn't matter. If it pushes, you probably need to send it back to the airstream and not atmo. I'm not 100% sure though!

^^^ wrong according to roadie...and it makes sense. I guess you have to vent before you hit the MAF to correctly meter air.

-Alex

 

most people who vent the valve to atmosphere are relocating the MAF to the pressure side after the valve... So, when the valve releases air, it's unmetered air.

That's kinda hard to do with the roots-type blower. I think you'll have to plumb it back into the intake tubng after the MAF in order to not loose metered air..

 

In this case (Eaton roots-tyle blower) the MAF is, and pretty much as to be, on the inlet side.

Still not sure how they handle it. Then again, since the throttle valve is -before- the blower on a Roots style setup, its also not clear to me why they even need a bypass valve... its not like they're going to get compressor surge against the throttle valves, since they're before the blower!

Weird setup...