Williams Air Scoop

[ChavyBoy]

Quote: Originally posted by Tomclio16v on 03 September 2003

Quote: Originally posted by ChavyBoy on 03 September 2003

Tom what is your view on this ??

it doesnt work. imho

(Ps my "lol" wasnt directed at KS post, it was me contemplating the impending discussion)








It dont work generally ??

Discuss !!

 

[rt172]

Quote: Originally posted by king.stromba on 03 September 2003

Rhys, did you have a look at that piping?

I couldnt find the piping you were on about. Were going to try the extra big B&Q this afternoon.

 

[Tom]

Quote: Originally posted by ChavyBoy on 03 September 2003

It dont work generally ??

Discuss !!

Not on cars no

if you figure out the pressure increase that you will get compared to normal airpressure, it is very small indeed. The air density increase that you can get below 70mph (highest possible legal speed) is very small.

the temp of the air going into the engine is a totally different thing. The change of air density with temperature is considerable, so a cold air intake is going to give you better gains than trying to catch some air in a vent/pipe of some sort.

 

[ChavyBoy]

Quote: Originally posted by Tomclio16v on 03 September 2003


if you figure out the pressure increase that you will get compared to normal airpressure, it is very small indeed. The air density increase that you can get below 70mph (highest possible legal speed) is very small.

So if this is the case why if you disconnect a ram air system on a motorbike does its performance drop considerably at speeds less than 50mph ???

After all this is just an extention of the car theory ! and motorobike engines are exactly the same as car engines be it smaller..

 

[BenR]

Quote: Originally posted by king.stromba on 03 September 2003


Ok so air travels from an area of high pressure to an area of low pressure. Basic science. The low pressure is in the engine caused by the downstroke of the cylinder (im not very technical i hope this is right). This creates a pressure difference that alllows air to passively move from the air inlet manifold to the engine (this is in the standard case). A normal filter (paper) impedes this air flow particularly as it gets old, and this is the principle of a performance filter. The performance filter is less restrictive and facilitates an easier flow of passive air down its concentration gradient from the airbox to the engine.

Now, from a non techinical viewpoint with my scientific hat on, i would have thought that if you can increase the pressure in the airbox, you will in effect create a greater pressure differential between the airbox and the engine. The greater the difference between the area of low pressure and the area of high pressure, the faster the air will travel (this is basic meteorology). This increased pressure differential may allow a greater flow of passive air down the pressure differential from thew airbox to the engine. So im not saying that you ramming air into the engine. Im saying you are trying to facilitate the normal process by increasing the pressure differential from the airbox to the engine.

However, this does in fact assume that there is less air reaching the engine than it actually needs. i.e. there is no point supplying 150% of the air required by the engine, as it will only ever need 100%. So if a standard Willy gets 95% of the air it needs (perhaps due to a poor inlet pipe that is restrictive), you could by increasing the pressure in the airbox suupply the extra 5% and get a performance increase.

This is only theory. Please feel free to shoot me down in flames. Also i know where only talking 1 maybe 2 BHP, but i feel that if you can find 1 or 2 BHP in a number of areas, it soon adds up.

Correct.

BUT, the principal is that you cannot create an increase in the relative positive pressure in the airbox.............there is no one way valve to contain air entering it to come out. THen you have to consider the massive volumes of air a 2ltr engine consumes, flow at rd speeds would have to firstly match this volume then exceed it.

In perfect theoretical terms, with a perfect ram system, at 100mph the max pressure you could theoretically attain is about 0.177psi........such a minute amount compared to atmos pressure.

The main benefit will come from cold air, as i have said many a time, THe supply of cooler air will facilitate a far easier gain in power. For example, a 3.3 deg C drop in ait temp is roughly a 1% increase in air density. Your intake tems will roughly be 80C.......half that and you can get a relative gain of 10% desity..........far better than any 0.17 psi as its closer to 2psi effective positive pressure.

Then there is the problem with actually creating the pressurised box, its bot just about a big funnel then plenham, it has to be precisely calculated to achieve the correct pressure fluctuations at the opening. Study a motorbike one and youll see.

Turbos can create artificial positive pressure simply because they act as a one way valve.....now way out but through the cylinders.

 

[Tom]

Ivan see above for answer.

(phew that was a close one)

 

[BenR]

Quote: Originally posted by Tomclio16v on 03 September 2003

Quote: Originally posted by ChavyBoy on 03 September 2003

It dont work generally ??

Discuss !!

Not on cars no

if you figure out the pressure increase that you will get compared to normal airpressure, it is very small indeed. The air density increase that you can get below 70mph (highest possible legal speed) is very small.

the temp of the air going into the engine is a totally different thing. The change of air density with temperature is considerable, so a cold air intake is going to give you better gains than trying to catch some air in a vent/pipe of some sort.

nice one tom!

 

[ChavyBoy]

Quote: Originally posted by BenR on 03 September 2003

Quote: Originally posted by king.stromba on 03 September 2003


Ok so air travels from an area of high pressure to an area of low pressure. Basic science. The low pressure is in the engine caused by the downstroke of the cylinder (im not very technical i hope this is right). This creates a pressure difference that alllows air to passively move from the air inlet manifold to the engine (this is in the standard case). A normal filter (paper) impedes this air flow particularly as it gets old, and this is the principle of a performance filter. The performance filter is less restrictive and facilitates an easier flow of passive air down its concentration gradient from the airbox to the engine.

Now, from a non techinical viewpoint with my scientific hat on, i would have thought that if you can increase the pressure in the airbox, you will in effect create a greater pressure differential between the airbox and the engine. The greater the difference between the area of low pressure and the area of high pressure, the faster the air will travel (this is basic meteorology). This increased pressure differential may allow a greater flow of passive air down the pressure differential from thew airbox to the engine. So im not saying that you ramming air into the engine. Im saying you are trying to facilitate the normal process by increasing the pressure differential from the airbox to the engine.

However, this does in fact assume that there is less air reaching the engine than it actually needs. i.e. there is no point supplying 150% of the air required by the engine, as it will only ever need 100%. So if a standard Willy gets 95% of the air it needs (perhaps due to a poor inlet pipe that is restrictive), you could by increasing the pressure in the airbox suupply the extra 5% and get a performance increase.

This is only theory. Please feel free to shoot me down in flames. Also i know where only talking 1 maybe 2 BHP, but i feel that if you can find 1 or 2 BHP in a number of areas, it soon adds up.

Correct.

BUT, the principal is that you cannot create an increase in the relative positive pressure in the airbox.............there is no one way valve to contain air entering it to come out. THen you have to consider the massive volumes of air a 2ltr engine consumes, flow at rd speeds would have to firstly match this volume then exceed it.

In perfect theoretical terms, with a perfect ram system, at 100mph the max pressure you could theoretically attain is about 0.177psi........such a minute amount compared to atmos pressure.

The main benefit will come from cold air, as i have said many a time, THe supply of cooler air will facilitate a far easier gain in power. For example, a 3.3 deg C drop in ait temp is roughly a 1% increase in air density. Your intake tems will roughly be 80C.......half that and you can get a relative gain of 10% desity..........far better than any 0.17 psi as its closer to 2psi effective positive pressure.

Then there is the problem with actually creating the pressurised box, its bot just about a big funnel then plenham, it has to be precisely calculated to achieve the correct pressure fluctuations at the opening. Study a motorbike one and youll see.

Turbos can create artificial positive pressure simply because they act as a one way valve.....now way out but through the cylinders.

LOL Ben must of copied this from someone else as there are no spelling mistakes in the text.

 

[iPap]

But running a pipe to the front of the car where the air is cooler is surely a benifit, as you are getting a direct feed of cool air which takes a straighter path than some original box setups?

 

[BenR]

lol.........you mean i didnt type teh once!

Still got all my millions of periods though.................

Damn, spotted one "now way out but through the cylinders.".....should be NO.

 

[BenR]

Quote: Originally posted by nickyb121 on 03 September 2003

But running a pipe to the front of the car where the air is cooler is surely a benifit, as you are getting a direct feed of cool air which takes a straighter path than some original box setups?

Path really doesnt matter at this level.

And read my post!!!! its all been answered!

 

[ChavyBoy]

Quote: Originally posted by BenR on 03 September 2003


lol.........you mean i didnt type teh once!

Still got all my millions of periods though.................

Damn, spotted one "now way out but through the cylinders.".....should be NO.

or LOL 5 or 6 times.

 

[BozVanDam]

Quote: Originally posted by ChavyBoy on 03 September 2003


LOL Ben must of copied this from someone else as there are no spelling mistakes in the text.

OCR is pretty advanced these days though

 

[iPap]

Wasnt suggesting better presure input just a shorter route, thus giving it less time to be heated within the engine bay?

 

[ChavyBoy]

In the same way an Intercooler works, so why not bolt on an Intercooler Ben to a N/A engine, surely you would get some gains by doing that ???

 

[Tom]

but then you restrict airflow too much

 

[king.stromba]

Ok what about this. A really long intake pipe that zig zags through the car (somewhere). Along side this pipe, another pipe conaining dry ice. The length of time the air was in the pipe (the zig zaggy one) the air temp would drop 5 or so degrees easily (maybe alot more). Ok so youd have to fill up each time you drove, but for track days anf the like........boooom. Dry ice is cheap, light and readily available. Bet if you designed a really good system you could drop the intake temp 10 degrees. What power gains would a ten degree drop from room temp give you?

 

[iPap]

f**k it, lets all get NOS, much easier!

 

[king.stromba]

Dry ice has a surface temp of -79 degrees centigrade. And it sublimes (ie goes straight from solid to gas, so no mess). It stays cold for ages. Am i onto something here? You could fill up with dry ice at the service station when you got you petrol, lmao, quick where is the patent office number......

 

[BenR]

use your aircon lol.

You could use a charge cooler filled with dry ice i guess, but using an intercooler would no lower the temp at all. You take in ambient temp air, send it through a large capacity intercooler, only to be cooled by.......ba dum, ambient temp air........heat soak can occur with it since its metal so you might get hotter air dependant on location.

 

[ChavyBoy]

Quote: Originally posted by Tomclio16v on 03 September 2003

but then you restrict airflow too much

No more than what is already there and this way you would drop the temp down.

 

[king.stromba]

How much power gain would you get from dropping the air temp by 10 degrees?

 

[BenR]

roughly 3%

 

[2 live]

some ppl talk a load of bollox on this forum

but fukkit

i find that an induction kit is worth fuk all wen its up against the heat generated by the engine on a valver/willy, thats y ive gone for a replacement k&n panel filter rather that an ind kit.makes a lot more sense than trying to eeeek out a few extra horses that arent there in te first place

 

[BenR]

erm, thats why were all talking about cold air ?

now im confused.....not that its hard to do lol.

 

[king.stromba]

LOL. Saturday night beer answers.WTF????

 

[king.stromba]

Friday night even

 

[Nick Read]

Ram air works and thats all Ive got to say on the subject. Maybe only a little but if does work. Just give it a try and see what happens?

 

[BenR]

*slap*

 

[Nick Read]

LOL