theboy

can someone with this knowledge tell me how much is

130 CFM (cubic feet per minute, ft3/min) --->can produce---> how much psi in a 3inch straight pipe?

130 CFM also equavalant to 61 Litres per second.

rotarygod

What is the reference pressure that it is flowing at? Cfm is measured in relation to a certain pressure and can't be used without knowing this.

theboy

erm... i am not sure what is the reference pressure. it should be atmospheric pressure index -----> into a 3" pipe

rotarygod

The problem is that you need a reference test pressure to determine flow. On my flowbench I'll test at a static pressure of 28" of H2O. Others use different test pressures. Even Holley measures their 2 barrel and 4 barrel carbs based off of differing test pressures so they can't be compared by just looking at the numbers. If you use atmospheric pressure as a test reference, you have no flow as there is no additional pressure.

As an example I can change the total airflow by varying the test pressure even though the cfm number stays the same. If I use a reference pressure of 14" of H2O and get 130 cfm and then change everything up to a test pressure of 28" of H20 and still show 130 cfm, the one tested at 28" of water is actually capable of flowing half as much air. This is why flow numbers are irrelevant without a frame of reference. Many people/company/places, do not give you the whole story as they are hoping that you won't know all of this. In the same manner pressure without flow is also irrelevant. You need to know both. You can have pressure but no flow but you can not have flow with no pressure.

130 cfm at a reference test pressure of 28" of H20 (or anything lower) will easily flow through a 3" pipe with no issues. Your engine flows twice that stock at redline so even a 2" pipe could flow the number that you are concerned with assuming it's at a reference test pressure that's pretty high. Why do you need to know this information? Is it for an exhaust pipe?

PoopSmith

Can produce pressure? Isn't more like how much pressure will I loose in "X" length of 3" pipe?

theboy

This is what i am trying to design.
what i am trying to achieve is 10 - 20 hp of gain. 4AT rx8. dun wanna break the gear box.
u think 2 option is workable?
and what is the hole in the airbox for?

rotarygod

That's not going to work. You aren't going to have near the airflow ability that you need. Here's a way to look at things. Let's just say that your engine is capable of using 300 cfm of airflow at redline. That's not exact but you get the idea. You want to install a device that can push I assume up to 130 cfm of air. I wish I knew the test pressures involved but something tells me that it's very low. That thing will be a restriction and cost you power. If you intend to make more power, you need to flow more than the engine can handle. Just using a rough estimate, assume that 1 bar of boost (14.7 psi) will take double the airflow. Any other boost level will be a direct relationship more in air. Theoretically. But it needs to be a number above what the engine already uses. That thing is not.

Is this an "electric supercharger"? Those things are a huge scam and are a waste of money. Don't get ripped off into thinking that those can work. How many amps of current does it draw? This is a dead giveaway as to it's abilities. You had better have a blower with the ability to pull several hundred amps of current to make any considerable power. I don't see it happening. Even a gas powered leaf blower isn't going to do much for you.

theboy

Rotarygod its 62 watt, 12V 4.5A. i get the picture what u are teaching me here. not that i don't like more HP, just that 4AT is well known that the tranny cannot handle 250 HP. so its not gonna be like a turbo or supercharge.

i am trying not to push it to 1 bar. and try to put it at a rate that the AF can handle. its like pumping extra air to get a stronger AF mix. Possible?

it is surely gonna be a low power charge, but like u say will it be as powerful to at least give 5-10 HP? if its less than 5HP its worthless.

rotarygod

It takes somewhere around 750 watts or so (don't remember exactly) to even equal 1 hp. 4.5 A definitely isn't going to do it. The point is that there isn't even enough power out of that thing to keep up with the stock airflow requirements of the engine let alone try to improve upon it. You will lose power if you install it. Those things are a complete waste of time and money. You won't even see 1 psi of boost, anywhere! You are not going to gain even 5 hp. You'll actually lose power. It can't even give a low power cahrge. It can give a less power charge though. It'll be nothing more than a system restriction. I'd throw the entire idea away and pretend you never even heard of it. Remember knowledge is power too. Those things aren't!

theboy

Hey bro i really learn a lot from u man. thanks for all the guidance. *enlighten*