DON'T BUY A Gen2 TURBO!

[Jeff]

I will not believe their little electric motor can output the required air. I just look at the wiring to realise it cannot possibly draw the level of current required to achieve their claim UNLESS it only achieves it's claim a little over idle when airflow is so low. Now they claim an increase, they don't say where in the rev range do they? I'm sure it would become a restriction at 7000 rpm but hey, what do I know

 

[Wattie]

I will not believe their little electric motor can output the required air. I just look at the wiring to realise it cannot possibly draw the level of current required to achieve their claim UNLESS it only achieves it's claim a little over idle when airflow is so low. Now they claim an increase, they don't say where in the rev range do they? I'm sure it would become a restriction at 7000 rpm but hey, what do I know

The more I think about it, the more I reckon the 5% comes from the intake tract and the paper filter alone...

IIRC someone claimed 15 bhp from drilling their air-filter box :?:

However, you can't charge $400 for a bit of drainpipe and a cone filter :thumb:

Stick in a 12v fan, securing it with a bit of duct tape, however... :grin:

 

[Wattie]

Here you go...

 

[GT4]

Errr.... How do you work that out? Why 0.4 bar assistance to produce 5% more power? I reckon 0.05 bar is about 5% increase in pressure

So, 0.05 x 3.6/2 x 7k = 630 l/min

Easily achievable with a 12 v electric motor running at 25,000 rpm (as they claim). However, I would be a little concerned about the life expectancy of the alternator if it's drawing that current all the time!

Actually, I wouldn't mind betting you'd get the 15 bhp just from that width of intake tract and open paper filter alone... What does a K&N induction kit give you?

The case I was refering to is my original premise of matching Turbo 1.4 bar total (0.4 bar additional)

I get 0.4 bar ASSISTANCE to produce 30% more power (to match Turbo)

So ADDITIONAL 5k LPM as stated.

Now I said that this is more than 3x a 240V / 1,400W (1.9PS) Dyson ASSUMING it actually is as efficient.

So if we assume the eCharger is a powerful same as a SINGLE Dyson (which it can't be, as it can't draw enough current at 12v) the it MAY give 10% gain (1/3rd of 30%)

You are, however, correct that a K&N and CAI would blow this garbage into the weeds.

You don't need an intercooler unless you are substantially pressurising the air: I don't think 0.05 bar will produce a measurable temperature rise tbh

I do need an intercooler as I am adding 0.13 bar minimum (I would point out that my dig was mainly at the warm air intake, the lack of IC simply underlined the "heath robinson" air)

I don't think VW spent a single penny (or cent) on the Mini BMW did, though...

You misread my "mini TURBO-SUPERcharger system" (note: a "mini" means small when not a proper noun and with "TM" next to it followed by "Adventure") - I ferer to the SMALL/TINY etc TSI system fitted to VWs 1.2 and 1.4 petrol engines.

As a final go at trying to prove this MAY work for your benefit, I will work from simplified energy principles (rather than volumetric analysis):

So, if we assume 25A is safe continuous current draw (!) in the car, this results in a 300W fan power. A 300W fan power will allow a FI of 0.028 bar (which I will also defer to you and assume it is quasi-static and requires no IC, but please, for goodness sake - SUCK IT IN FROM OUTSIDE THE ENGINE BAY!!)
Note: 25A at 60% alternator efficiency will require an additional continuous load of 0.79 PS from the 14V alternator.

The 100% efficient conversion of 0.028 additional bar FI to a 996 3.6 NA engine rated @ 320 PS gives an additonal 2.1% gross gain = 6.72 PS

Now deduct the 0.79 PS production load, gives a maximum possible 5.93 PS gain

This does assume all the gubbins works (does not detract from Porsche's fine engineering), no heat is generated and the unit does not add any additional friction or turbulence to the air flow, it can thoughput 102.8% * 11,250 LPM and the actual fan assembly is 100% energy efficient.

As you say, get a K&N fiter!

 

[Wattie]

You might be better off with one of these mate :thumb:

 

[GT4]

You might be better off with one of these mate :thumb:

... I guess it would produce more power! (you are suggesting you shovel more air in aren't you?)

 

[Wattie]

... it would produce more power!

:floor: :floor: :thumb:

 

[GT4]

Wattie, when is the Rangey getting fitted ?

Don't worry that LR's aren't specifically offered in the Vehicle Makes list, it won't work in exactly the same way as it doesn't work on any other make.

 

[Wattie]

Wattie, when is the Rangey getting fitted ?

Don't worry that LR's aren't specifically offered in the Vehicle Makes list, it won't work in exactly the same way as it doesn't work on any other make.

It already has the real thing on there and I have the fuel consumption to prove it :thumb:

None of this nambi-pambi hairdryer nonsense for me :grin:

 

[GT4]

None of this nambi-pambi hairdryer nonsense for me

- have I convinced you then?

Thanks for the "Devil's Advocate" trial by forum, though!

 

[theogeor]

Wattie, when is the Rangey getting fitted ?

Don't worry that LR's aren't specifically offered in the Vehicle Makes list, it won't work in exactly the same way as it doesn't work on any other make.

It already has the real thing on there and I have the fuel consumption to prove it :thumb:

Fuel consumption ??? I though your RR was very fuel efficient and you said that you can do close to 1K miles with one tank :dont know:

Theo

ps; (maybe 1K its with a trailer fuel tank at the back :floor: )

 

[wizard993]

Fuel consumption ??? I though your RR was very fuel efficient and you said that you can do close to 1K miles with one tank :dont know:

Theo

ps; (maybe 1K its with a trailer fuel tank at the back :floor: )[/quote]


Maybe 1k KM's as they are about as fuel efficient as Concorde was.

BTW - Anne Summers are now stocking these electric "superchangers" at less than 1/2 the price of the one on here....just send the wife/gf in to buy one :grin:

 

[Wattie]

Fuel consumption ??? I though your RR was very fuel efficient and you said that you can do close to 1K miles with one tank :dont know:

Theo

ps; (maybe 1K its with a trailer fuel tank at the back :floor: )

I think you may be thinking of someone else :dont know:

either that, or it was an attempt at humour? :wink:

At 15 mpg, it would need a rather large tank!

 

[wizard993]

"I think you may be thinking of someone else :dont know:

either that, or it was an attempt at humour? :wink:

At 15 mpg, it would need a rather large tank"


Hook, line and sinker :thumb: :floor:

 

[Achtung]

An interesting subject but a few other things to think about-

You are both assuming that a normally asperated engine runs at 1 bar induction pressure at the cylinders. Actually it runs at a vacuum. This will have a large effect on your calculations.

Also you are not applying Boyle's law and Charles's law which are crucial with regard to the effect of temperature on a gas when calculating pressure and volume.

Two other factors to be looked at is Reynolds number and its effect on gas flow and the change in compression ratio, and whether an normally asperated engine will allow running on increased compression ratio. (what physical cylinder head differences if any between a stock engine and an existing turbo?)

As an aside, to ease the burden on any "electrically" driven supercharger you could make it more efficient by drawing colder air ( helps regarding Charles's law) and by placing the air intake in the positive pressure airflow coming over the roof of the car and down towards the spoiler.
This should reduce the motor current draw and give boost levels proportional to car road speed as another bonus.