Blower on demand

[Racer X]

Why don’t you just adjust your driving style instead of fabricating such complicated system?
Is this for a replica of Mad Max Falcon Interceptor? AFAIK that was fake

Driving style isn't the issue. I'm not building a race car. I actually enjoy the engineering challenge of my circumstances. I'm an historic preservationist in San Francisco, I have the steepest hills to climb with a load of lumber and tools. I mean 29% grades and steeper. Then you have the Uber driver that decides to throw on the flashers and double park in front of an empty driveway. Now I have to stop and wait to go around with that load of lumber on a 29% grade. Ya I need torque. When it's moving on these hills it's turning about 2500 rpm at 25ish mph. Granted there are a lot of other ways to go about it but I got these parts for super cheap so I'm giving it the old college try. Blower, intake and two intercoolers for 700 bucks...Hmmm. Just got a new mill and a tig welder... never had a supercharger before ... gain a 100 ft lb and a 100 hp ...You know that grin that come across your face when a plan comes together. Yeah I'll give it a shot. Mad Max, hardly but I might get one of those switches just for fun.

 

[Racer X]

No sense to clutch it. I doubt blowers are getting a clutch anytime soon. They use less than 1/2 hp at cruising speed with the bypass open. A clutch is an unecessary, problem prone and expensive addition.

Even Nissans 2.5L Hybrid driveline for the Murano and Pathfinder used a clutch-less blower.

Best fuel economy option would be a turbo with a vacuum actuated part-throttle open waste gate that was sized large enough to prevent any additional exhaust backpressure from building until the intake manifold vacuum dropped off to practically zero.

Well Eaton is already building them into the housing before the snout so you'll have to talk to them about that. However since I'm only shooting for about 6 or 7 lbs of boost. I'm thinking the clutch might not be needed with the extra bypass volume I've got. Besides it triples the price of my budget build. They have us Mercedes owners by the balls on some parts. I'm glad I have twin turbos on mine. So far it's been bulletproof.

 

[Racer X]

The Previa used a 1.4L roots blower like their full size cars. I had a Corolla with a 1.2L blower that later got a 1.4 from a car. Their blower clutches work nicely, but it's tough to draw decent airflow through stationary rotors. On my 1.6L I used a Vortec mondo bypass valve that had a 2" inlet. Even with that, the car struggled with the blower off as with any sort of load the bpv would close. Full time blowers like the Whipples on both of my trucks have bypass valves and when empty they get NA fuel economy so my input is that you're overthinking this having been down that road. In addition, the Toyota blower pulleys are way too big to make any sort of boost on these motors.

I may not go with the clutch, but my idea was to make a jack shaft to adapt it to using a second dedicated belt to drive the charger with the stock pulley on it. In this configuration I could make any ratio changes I want at the jackshaft so I can leave the crank and the blower alone.

 

[Racer X]

LOL, I was thinking "Mad Max " when I read it the first time.


How you going to get air through a blower that's turned off?

I know some like Mecedes have systems that bypass the blower during light throttle/cruise but you're talking electronically controlled and gated blower housing/intake that have an air path around the blower mechanism coupled with direct port injection.

Bingo! add coil near plug and A/C chilled air to water intercooler at the intake to the blower and another one under it and that's the whole picture.
Upon continued research into this build I found that my system is very similar to the Dodge Challenger SRT Demon. I'm using Laminova tubes in the charge air cooler for hood clearance and a suburban rear air evap to cool the water but still similar. I'm very familiar with Mercedes as I have a 300D turbo and a CL600 Renntech that I do all my own wrenching on. Charge air temps were always an issue without the chilled water on the 600 she's tuned pretty hot. Bulletproof these days though.

 

[Carlaisle]

The A6 compressor was (I think) the largest displacement AC compressor ever put on a production car which means it probably has the heaviest duty clutch.

 

[Schurkey]

Or just install a turbocharger, which provides boost based on exhaust pressure/velocity. In other words, it does exactly what you want without needing a clutch or the control system to engage/disengage.

Step on the throttle...you get boost. Drive easy...no or very little boost.