So, I know that "I/H/E" means intake, header, exhaust. What I'm unclear about is what "intake" means...does this mean a replacement for your stock airbox (e.g. AEM), or does it mean a replacement for the intake manifold (e.g., Skunk2 Pro, etc)?

fm

 

replacement for your stock airbox. intake manifold's a fun upgrade though too, just not as basic...

 

yep, intake manifolds usually go under IM or the actual intake manifold model/make.

 

just to throw it in because of the intake discussion. Dont waste your money on a cheap short ram. Get a drop in (k&n) or a cold air. Its been proven those are both better than a short ram

 

Thanks all...you've confirmed what I've suspected. Just wanted to be sure.

fm

 

disagree!!


I would much rather have a whale ***** than a drop in or CAI

 

id only go with a cai if its designed with a water bypass to prevent hydrolock.

 

Don't forget that the throttle body is also part of the intake system.

Intake includes the actual air box/tube and filter, the throttle body and the intake manifold.

 

True, although when someone says they have I/H/E on their car, they mean just an intake (filter / short ram / cold air), while I/H/E/IM would mean they have a different intake in addition to intake manifold (and probably throttle body too).

 

the "i" in i/h/e surely means intake, the tube or piping off of your throttle body...
sri (short ram intake), or cai (cold air intake).
no big differences, the cia overally is better for top end power cuz it pulls more cooler, denser air intake
the motor, vs the short ram where it's pullin engine bay air, usually hot, less dense.
cai= a bit more power, sounds cool lol, looks nice under the hood, can be pricey tho
sri=faster throttle response, no weather related dangers, cheap, better than a stock airbox by far
super street mag proved this in the november issue i believe, 150hp the test car had with stock box
and 157 after a sri was applied, i would say 159 maybe 160 with cai..
-hope this helps man

 

cars with cold air intakes do not like puddles. Short ram for the swim win

 

no!

short helps top end, while longer helps low end. just like the IAB in gsr and h series motors.
when you need the top end the iabs close making the air go through a shorter path to the combustion chamber. and a longer path for low end.

depending on how the car is built should decide if you want a short ram or cai.

 

I wasn't aware of this...do you know of any writeups that help explain this? My civic si has a CAI, but it would be nice to understand just how this benefits the low end power.

Thanks

 

im afraid the diameter of the piping is the bigger factor in low vs high end. larger diameter is better for top end cuz it can flow more air.......but doesnt force the air to increase velocity and hurts low end, smaller diameter is better for low end cuz it forces an increased velocity......but it chokes the engine up high cuz it cant flow as much air. the same principles apply to headers and exhaust systems. i dont think length has much to do with it on the intake side because there is no collector(like on a header) which causes scavenging and helps pull the air out.

 

sure diameter is the major factor because of volume. shorter is velocity which in turn is volume. well for the most part

 

i nvr heard this either, sure alot of factors should be considered, but i'm sure it's not a b18c he's runnin, plus i'll bet w.e motor is, isn't built so i was providing basic info, in which i found on h-t...so ur sayin h-t is wrong not me, thanks tho

 

velocity and volume are the 2 things that matter here. you need velocity down low and volume up high.

try this experiment:
open your mouth wide, put you hand in front of it. blow

now pucker ur lips hold ur hand in front of your mouth and blow with the same force as before.

with your mouth wide open it takes little effort to move alot of air. with your mouth almost closed it takes more effort because you are trying to push the same volume of air thru a smaller hole BUT the air is moving faster.

now with a standard multivalve engine(more than 2 valves per cylinder) you have alot of valve area vs displacement. at high rpm this is great, it allows the engine to flow more air. gasoline engines become more and more volumetrically efficient as rpm increases(to a certain point). what that means is that the cylinders at 2000rpm arent being filled with air as completely as they are at 5000rpm. honda has remedied SOME of that with vtec. but lets stick with a non vtec engine for now.

so at low rpm, you need your intake velocity high so that even though the engine isnt flowing alot of air, you are still filling the cylinders more completely. to get velocity you need a smaller diameter(remember the experiment). now as rpm increases you need a larger diameter so that your intake will be capable of flowing enough air to fill the cylinders.....and at high rpm you have both velocity AND volume. thats the easy part..........keep going up in size til you stop seeing gains. the problem is that you lose so much velocity with a big intake that you are hurting torque(which most hondas dont have much of to begin with) and torque is what makes a good daily driver. so on a racecar, intake size is too easy, you know you want your power up high so you keep increasing intake size til it doesnt help anymore. the trick is finding a size(and to a much lesser degree length) that helps in both areas since most of us on here drive our project cars daily.

for the most part length applies to header tuning. long tube vs shorty. the rule is longer, smaller diameter headers are better for low end torque, short, larger diameter headers are good for top end power. and then collector size and arrangement comes into play(4-1, 4-2-1, 180 degree.....)

 

Man I had that one time when it was raining badly and scared the hell outta me. So I bought a cover to divert the water away from my intake haha.

 

Thanks for the added information. It helps to understand it a little bit better.

 

I have a CAI on my si, and I do not have an air bypass....however the intake sits above/behind some plastic that blocks almost all road water. I have been driving in water numerous times this year already, with some area's being more like small rivers in the road and I have had zero issues whatsoever.

 

i think someone did a test and it required 8oz of water in one cylinder to hydro lock. that could be wrong tho

 

Yeah, I had a plastic cover when I got my car, but somethings happened and I had to remove it, thus leaving my intake open to everything that hits it underneath. I bought another 1 and installed it after I hydro-locked like crazy during a bad storm.