i need a nice functional hood

[fiveohwblow]

What is a TW sgt1? I'm mental blocked on your abbreviations, but I think I get the picture. Glad you agree. This is not a flame! Bear with me here (no pun intended) Anyway, here's the deal. All an engine is, simply put, is an air pump. It sucks it in, compresses it, and spits it back out. The faster your engine is turning, the more air it needs. Just like the old muscle cars, the power band is starting to really crank at 80mph, and he has made it far easier for it to get the air it needs. The more efficient your "ram air" design is, the easier it is for the engine to suck it in- and the deeper in the power band you are, the more obvious it will feel.
Consider the internals of the operation: a crank is spinning at say 3000RPM so it makes 50 complete revolutions per second. And if we know that about the crank, we also know that the pistons are moving at that same speed, just in a different direction. If that is true, than the air in the chamber is being cycled at that same speed- every time the piston comes up to TDC and goes back down a set volume of air enters the chamber and is evacuated. If a hypothetical crank scribes an arc of, say, 4" radius, 50 times in a second, using a simple formula we can determine that if it were going strait instead of in a circle, it would cover over 657 feet per second, therefore over 39,438 feet per minute, therefore over 2,366,304 feet per hour, therefore over 448mph. Therefore, the engine is trying to suck air in at over 448MPH as well just to maintain the operation. How do you think that [air pushing air] into the engine at 80mph is going to affect that scenario? The only way to do it is with forced induction, and it isn't uncommon for a centrifugal blower to spin around 70,000 rpm. Compare that to the 3000RPM our hypothetical engine with the tiny 4" crank is pumping air, and see why they make so much boost. "Ram air" is a very cool sounding, yet inappropriate name for what is really just a more efficient cold air intake system.

You gotta give this man respect for knowing what he is talking about.

 

[stangbear427]

You gotta give this man respect for knowing what he is talking about.

Thank you.

I hate to open a dead thread however I am curious, what happens when it rains? Do you pull the water into your inlet tract? I'm interested in a ram air hood but my vert is a daily driver and WILL see rain unfortunately. Thanks - Peace all.

I drive in the rain all the time, this is my main vehicle. No problems. Snow either, for that matter. However, I have observed that it's a good idea to shut the car off at drive through car washes, because it does develope a bit of a rough idle if I don't, I'd assume due to the massive amounts of water placed right there for the engine to suck it in. As long as I turn the car off, it's fine.

 

[Lyncher]

Thank you.

I drive in the rain all the time, this is my main vehicle. No problems. Snow either, for that matter. However, I have observed that it's a good idea to shut the car off at drive through car washes, because it does develope a bit of a rough idle if I don't, I'd assume due to the massive amounts of water placed right there for the engine to suck it in. As long as I turn the car off, it's fine.

that didnt make sense?...you said its not a good idea to shut the car of but then you said as long as I turn the ar off, its fine... maybe i just read it wrong..idk lol

 

[_jb_]

that didnt make sense?...you said its not a good idea to shut the car of but then you said as long as I turn the ar off, its fine... maybe i just read it wrong..idk lol

You read wrong. lol

 

[stangbear427]

Yeah, slow down a click Lynch. To reiterate- shut it off in the car wash or it'll suck in lots of water and soak the filter, which will mess with the MAF and make it idle like a POS for awhile. However, driving four hours strait in pouring rain on the highway has been fine on repeated occasions.

 

[_jb_]

Yeah, slow down a click Lynch. To reiterate- shut it off in the car wash or it'll suck in lots of water and soak the filter, which will mess with the MAF and make it idle like a POS for awhile. However, driving four hours strait in pouring rain on the highway has been fine on repeated occasions.

I think it's pretty cool driving in the rain. Somehow the wind must move the water over about two inches from the scoops.