Electric fan - supercharger!??#@

[MO]

There was talk in the flaming forum of people getting around with electric fans in there intake to add a turbo like effect to your vehicle.
I think this is good to laugh at but not something that would work - any one with opinions on this - or even better a dyno result.


The flaming thread is here:
http://www.fordmods.com/phpBB2/viewtopic.php?p=102599#102599

[Spork]

I'm going to say this slowly. Oh....My....God.

Lets engage at least half a brain here.

Say we have a 4 litre engine spinning at 6000RPM and lets say the volumetric efficiency is around 70% That means it is sucking in 140 Litres of air every seccond. (300 CFM)
To give you an idea it's like sucking half the air out of your fridge, every second, how much air would some little PC cooling fans in your intake flow? Not much. mayby about 5l/s if your lucky. Of course some suppliers say their 'superchargers' can flow that ammount of air. But at what pressure differential? 140 L/s at 15psi is VERY different to 140L/s with no pressure rise.

Also you cant get something for nothing. Electrical power comes from the alternator which is driven by the engine. The more load on the electrical system the more the alternator loads up the engine. This will be ok if your electric supercharger is pumping in more air and generating more power but there are losses involved, ie the alternator is 90% efficient, the supercharger motor is 95% efficient, the turbine is 60% efficient, the engine is 35% efficient. All these multiply together to give a very poor efficiency in general for these type of superchargers.

The argument some suppliers of these superchargers use is that it only gives you more power at low RPM with part throttle. But what the hell is this? it's not going to make your car any faster. As soon as you put your foot down you have way over exceeded the 'superchargers' capacity.

So while 95% of all electric superchargers are rip off crap. There are a few that are designed correctly.
They are typically only available for small (<2ltr) engines and work by storing up charge in a large capacitor over about 5min of driving, then only when a certain throttle/RPM threshold is reached they kick in and provide mayby 5psi for about 20 sec. Then they have to be recharged. These things draw about 200A at a time and reccomend that you have a larger alternator. They also cost at least $1000 plus wiring.

So if you see a $75 'supercharger' that has tiny little wires coming out of it then its s**t.

[MO]

I think we should forward this info to Marmo.
His friend has got a fully sik ba xr8 with this xtreme modification - it goes real hard he reckons.

[bentles]

pc fan u say?

lol the 80mm ones shove like 30cfm MAX


120mm can shove up to 110cfm or so but even still if the 4.0 sucks 300, if u got enough fans it might do something.

however i still wouldnt think it would do much.

[bowsaw]

What a load of crap, rather buy a Hiclone, .

[Spork]

[MO]

Dont get me wrong - this is not my idea - MARMO brought it up and reckons his mates fully sic xr8 has got one and it goes real hard. I just wanted to bring some credability to my suggestion that it had no chance in hell of working. Please note the flaming topic was titled 'Dreamers' - and it think that pretty much sums up this electric fan supercharger idea.

[stockstandard]

[Marmo aka GRNGOB]

well i was jst going on what he told me i will try and get some pic's of it, it also had i think a 75hp shot of nos but that has eben removed...