okay, can you guys estimate how much CFM your everyday single turbo setup requires to suck into the manifold?

I know 6 Psi is about normal, but what is that in CFM? because I had this question that had me thinking;

say when you're driving on the freeway @ 100km/h, no doubt you're going to get a fair bit of air rushing into your intake, and no doubt your engine will automatically get a bit better air, with help of the pressure generated by the head wind, so if we make a comparison between say 0km/h wind to 100km/h wind being sucked into the intake, how much more horses do you think you're getting whilst this 100km/h head wind is forcing itself into the manifold?

I'm just wanting to know if anyone has some sort of number in terms of CFM for the single turbo set up?

Dave, maybe you know?

PSi is a measure of volume and Cfm is a measure of airflow rate, so I believe it's difficult to really get any numbers from any conversion of PSi to Cfm.... I'd say you'd have to ask someone who knew... like Dave :).

Somehow I have doubts your power rating is increasing while you're on the highway. Please correct me if I'm wrong :oops: , but there would be no where NEAR enough air to create the air density and pressure required for CFM or boost.. If there was a huge hole in your bonnet, and maybe no filter or MAS sensor then it might... if you were travelling at 200k. But I'm not an expert.

As for the last question, not a damn clue. :D

The advantage of CAI and stuff like that is to give the engine a decent source for cooler air. Some people talk about a 'ram air' effect which would be like a turbo but it's not. A NA engine will suck what air it needs and it's still at one atmosphere. There would be little gain if any. A supercharger or turbocharger is different. It's being forced and the air can only go in, not out, and it's under pressure.

That's what I was trying to say. :D

This reminds me of an idea I had when I was younger! Let's just create a sealed intake system which uses pressurised pure oxygen!

VERY GOOD IDEA,

but just becareful, Oxygen is very combustable! don't try it to your car, your engine will knock as the fuel and oxygen will combust much easier.

oh yeah, come join us on the electric turbo debate.

Yeah I know...it's not as easy as it sounds! But, you wouldn't really need much compression at all ('cause you'd have free oxygen atoms already!!!). All you'd need is a safe way to mix the oxygen and fuel together and have it ignite at the correct time! Well...that was my theory anyway. Just think of how much power you could get out of it and how much cleaner the emissions would be...the best of both worlds!

You wouldn't even need an oxygen bottle either. You could have a heat shielded oxygen generator under the bonnet! 8) It'd never happen though...too many safety issues :(

wow, you got some real neat ideas there, more R&D needed. but oxygen is very dangerous, try N2O/LAUGHING gas.

oh on the other hand you could just install a NOS kit, which they've already done their R&D.

You know, i've always had a thought, What if you design a device that will compress air when you're braking or slowing down by attaching some sort of turbine to your axles. and when this is compressed, you can trigger to release this stored energy straight back out again when you want to accelerate say, now this could be ejected into the engines or drive some sort of turbine which will then help out the engine a bit... hows that sound?

but this is just a copy of the already existant idea for Trucks, they store braking energy into power cells and it does something else... i forgot. haha

Yeah...I wish I had the $$$$ for some R&D...but not going to happen for me :(

This is an excellent concept.The air for braking idea sounds sensational!! I have a ducted fan used for model aircraft( 50 cm impeller/fan driven by an OS 91 VRDF engine to create a sort of turbine/jet engine effect. Spins at 30,000 RPM) Been pondering how to adapt this to an air intake on a Magna. The obvious problem is that once the air pressure behind the fan exceeds that coming in, it will work against the fan to slow it down. Have considered flywheels and various weighting to achieve a compression effect, but thats as far as my brain could manage(What day is it?) I suppose that's why the turbo driven off exhaust gases was invented. But don't stop thinking laterally! That's a great train of thought.

Those new electric cars use a system similar to what you are saying. They use regenerative braking in that they have a generator hooked up to aan electronic clutch that disengages in proportion to your brake action, thereby running the generator which recharges the cars main battery. If you emergency brake then the generator comes online and the brake pads operate to slow the car that bit more.

You cannot use a non-displacing pump to force induction your car. The back pressure of normal fan blades is very small, well it is in proportion to your blade area you can see this by hugging a pedastal fan it doesn't push you back much does it? In comparison if you get the end of a air hose in a workshop it really makes a mark in your hand when it is free flowing.

So compressed air in a cylinder? Well you could use braking to run a positive-displacement pump that fills your surge tank with air. Big safety issue in an accident thought? Trucks use them for brakes but you should see how tuff those things are incase of an accident. ie too heavy for a car.

Oxygen - well besides being highly explosive when compressed it is also very unkind to engines. The energy liberated from even a small amount of pure oxygen burning with fuel (and why would you bother with CxHx fuels when you could use hydrogen) burns so hot that it melts metals, ie propane torch!

So that is why they use Nitros Oxide it is safer when compressed burns cooler and is adaptable to normal fuel systems.

Did you know that Rollsroyce turbine engines built a turbine powered car? Imagine just one big humungous turbo, !super lag! apparently the driver would brake and accelerate at the same time when entering a corner cause the turbine would take so long to spin up that as he exited the corner the power would come on and the car would go tearing down the track.

Keep thinking of new ideas though, necessity is the mother of invention and everyone needs more power :D

[quote:28c9d6e653]A guy called Otto once thought "Hey what if I use this steam piston engine to compress and ignite kerosine" he didn't survive the first experiment but his mate Diesel picked up where he left off and invented the compression ignition engine[/quote:28c9d6e653]

The previous quote is historically inaccurate.

Oxygen - well besides being highly explosive when compressed it is also very unkind to engines. The energy liberated from even a small amount of pure oxygen burning with fuel (and why would you bother with CxHx fuels when you could use hydrogen) burns so hot that it melts metals, ie propane torch!

So that is why they use Nitros Oxide it is safer when compressed burns cooler and is adaptable to normal fuel systems.

??? :? Oxygen is basically all that is being burnt when the air/fuel mixture is compressed and ignited. During the compression stroke, the Oxygen is seperated from the rest of the Hydrogen/Carbon/Nitrogen that's in the air.

yeah but of the air that is used, only a small part of it is actually oxygen. hes saying if you used the same volume of pure oxygen it would be too powerful and **** everything up.

Yeah, I get that bit....My original idea was to only use the same volume of Oxygen that actually gets burnt, not the same total volume of the air that normally gets sucked in. Hence, it would only be a very small volume of Oxygen that's used.!

Yeah, I get that bit....My original idea was to only use the same volume of Oxygen that actually gets burnt, not the same total volume of the air that normally gets sucked in. Hence, it would only be a very small volume of Oxygen that's used.!hahaha if that was the case you would get absolutely no performance gains. all youd have is a very skinny wallet, and the exact same output.

Just strap a jet onto the roof of your car ;)

Or in the boot.... Then youd have a cool car ;)

Yeah, I get that bit....My original idea was to only use the same volume of Oxygen that actually gets burnt, not the same total volume of the air that normally gets sucked in. Hence, it would only be a very small volume of Oxygen that's used.!

Another problem is that you need all that other gas in the engine, to expand when it heats up. It's the expanding gases that give us the power. I think if you could inject a bit of oxygen into the intake charge, the oxygen rich air would give off more energy (because you can burn more fuel), which would give more expansion, hence more power.

To answer the first question about the "boost" given from the ram air effect, it's calculated using the formula:
P = 1/2 x air density x velocity^2

So at 100km/h (27.8m/sec) the dynamic pressure is:
=1/2 x 1.225 (approx density for air at STP) x 27.8^2
=472Pa, which is equal to about 0.07psi. Not really worth writing home about, is it?