Vlad

Any idea how much it's going to cost me to put clutch for supercharger?

I don't like the idea of wasting fuel all the time. So I want to have some kind of on/off button on a dash, so I can engage or disengage supercharger at will. I did some research on internet and find out that it's doible. 2 things needs to be introdused to original SC design - clutch itself do disengage SC, and intake air bypass.

As I understand none of this is part of current Stillen design in development... Any ideas are any other producers offer such things?

joust75

iTrader: (1)

AMG does this for Mercedes Benzes. The supercharger has an electro magnetic clutch that engages under heavy acceleration.
Really trick and espensive! They say the on/off switching is seamless and imperceptible.

I would not think this technology would be available at a reasonable price for years.
But thats only my opinion. We can only hope!

Vlad

I find out that Blitz Japan is makin such a kit for Celica:

http://www.turbomagazine.com/features/0211tur_celica

it has ECU operated clutch. So, it's I guess it's not that difficult to produce such a kit?

Chebosto

iTrader: (43)

i'm sure once you have boost, you wont want it to go away, trust me. its really fun to have.

the problem with the clutch type engagement for the SC is that, sure under heavy acceleration you could engage it, but the power lag would sort of defeat the point.

the reason the SC is on there is that there would be a linear power output through out the rpm range. even if you wanted to boost at low rpms (3k) , the boost levels would be low anyway. i.e. 1-2 psi until you get to around 5-6k would you get around 5+ psi

the way Vortech/Stillen SC kit for the maxima, the aux fuel pump would only turn on when it sensed positive boost in the vacuum lines and then the aux fuel pump would turn on to provide the added fuel when boosting. that's mainly where the fuel waste is generally.

with the FMU discs that were provided from Vortech, the kit usually ran fairly rich based on generic boost applications, but you could get smaller discs to lean out. but then you risk detonation from fuel starvation...

your clutch engagement idea is kinda neat, but if you mush the gas hard at say 4k when you're on the freeway, it would take a while for the clutch to disengage allowing the blower to start creating pressure throughout the system and then you would only get slight amounts of boost until redline....

if you drive normal with the car with a blower on it, fuel consumption only goes down like 3 mpg... and most of the time, the boost is venting out anyway via bov when you're driving normal on the freeway... no addition fuel pressure raise..

what would be neat would be a coasting pulling, so that when you are boosting and you let off the gas to switch gears, that the blower keeps free spinning to maintain the boost, and not slowdown due to the reduced rotation from the crank pullies....

stillenguy

After speaking with the R&D manager at Stillen, I've learned why a clutch wasn't needed for the 350Z Stillen SC.

At less than 75 percent throttle, the SC bypass is open allowing normal airflow through the engine and uses the stock Nissan fuel mapping. Only at the top 25 percent or so of throttle does the engine go into positive boost, requiring more fuel to prevent detonation and engine damage.

In terms of the MBZ Kompressor, to the best of my recollection, it uses a clutch at idle and with the foot on the brake. The minute the accelerator is pressed, it's engaged.

"SC clutches really only work in Mad Max," R&D manager.

The bottom line is a clutch on an SC can make for an unreliable, dangerous system...not to mention, yes, expensive to develop, engineer, and keep up. In the long and short run, it's simply not worth it.

Don Weberg
Marketing Coordinator
STILLEN

Vlad

So does it means if use throttle at less then 75%, fuel consumption will remain exactly the same as without SC?

3 mpg extra Chebosto mentioned is exactly what I want to avoid. 19 mpg hi-octane fuel consumption can make me bankrupt without going to 16... I (as many others) have a family to feed, so if I need to pay all the time for the 25%spiritual drive, I wonder where I gonna get money for that...

Don, can you tell me what the plans for 5AT models? Will SC work withou additional transmission enforcement?

Thanks

AKAkracker247

stillenguy...How much horsepower will a stillen supercharger add, and how much torque will they add? And will the gas mileage stay exactly the same under 75% throttle?

Thanks in advance..

menehune

stillenguy, I have a question. Why did stillen opt for a screw-type compressor instead of a centrifugal compressor? Wouldn't there be more room for the latter without hood modification?

Thanks in advance...

stillenguy

Hey Guys!

To answer all your questions, here we go...

The SuperCharger will use a tad more fuel at less that 75-percent throttle, however, we haven't tested yet to find out exactly how much. But the bottom line is, it's an Air Pump, so it's naturally going to push more air into the engine, therefore calling for more fuel. Unfortunatly, R&D never got the chance to actually test a 350Z for efficiency.

Superchargers will be available for Automatic Transmission cars, however, the boost will not be as high to maintain the integrity of the auto trans.

R&D chose the Roots style over the others because of its reliability and efficiency. Roots is the preffered design by OE manufacturers because of the same reason.

I hope this answers all the questions....an FYI, my schedule here at Stillen is very sporadic, and as such I'll not be here from tomorrow until Monday, so if I don't respond really quickly you'll know why.

Thanks again!
Don Weberg
Marketing Coordinator
STILLEN

Gin262

Ok, that bothers me. This may be an ideal solution for straightaway 1/4 blasts and street driving efficiency... But for autocrossing (and maybe road racing /shrug) this just sucks. Coming out of a corner I don't want to have to worry about whether i'm near 75% throttle and am going to have to compensate for a surge of torque. I got away from peaky power (Celica GT-S) and power lag (Eclipse GSX) for a reason...

Blake

Gin262

Of course you mean they have it written down somewhere in a log book taken during long-term testing... right?? Or maybe they lost that part of the logbook... at least say they did some long-term testing. Please!

Blake

Chebosto

iTrader: (43)

There would be no benefit for AutoX with a blower. it would just cause more problems as far as power xfer and traction... hot lapping on big tracks its pretty good, but you'll be at the high RPM band the entire time, most of the boost would be vented out, and a blower is only really good for is when you slow down for a sharp turn and accelerate out of it...
this surge of torque you're talking about isnt dramatic as it is in a turbo car,
again, the SC provides linear power gains, so if u mush the gas at say, 40 or 50 mph, the acceleration depending on rpm will be gradual.. you will feel the push on the back of the chair.. but its not going to be so insane that the wheels break traction... thats only if you dump the clutch and spin the tires from the line, and even then will u get boost at around 3k rpms.