bighead2267

that's an impressive improvement. about the video you recently post. it will be more convincing if there is before and after the tube is install.
also, mind me asking the diameter of the tube?? thank you

545IblupasdU

True, I didnt think of doing any test when there was nothing there, especially since it was pretty much an experiment that i didnt think I could get to work.The entrance to the airbox is off to the side pretty much right behind the headlight......any air going into the kidney is going straight back to the radiator no air can be rammed into the box without something like the pipe guiding it. But yea It would be a more complete test showing the before result with nothing passing through.

The diameter of the pipe is 3".....what I had lying around....wonder if I should do one with 4 inch?

bighead2267

i guess it's time to Home depot shopping.

Seanaabrown

hey, id like to do the same thing
how big is the pipe size,
what is the diameter size please

FormerE30Owner

I am afraid that your estimate is not based on results which would be considered statistically signiifcant. You need much more before and after data to establish if the difference in mileage is really significant and not just due to normal variability. The difference in air pressure at the inlet of your air collecter is probably not more than if the barometric pressure had changed that day.

Any small benefit that you might have gained, would be negated by the small decrease in overall coefficient of friction due to the modification of the air intake. IOW, you increase the drag by 'collecting and raming in' more air.

Respectfully, Bob P.

545IblupasdU

If thats the case then everyone who has purchased the RPI ram air which is basically a shovel that doesnt guide or force any air into the intake box have been robbed! At the very least my ram air is a true ram air. And with over 2000 highway miles of testing after the installation my fuell economy went up. by 3+ miles per gallon. Those are my results! The same air that was going to hit the radiator went into the pipe.......its not like I collected some extra air from another area to change the drag. I would think that air that is getting sucked into the engine has less drag than air hitting the flat surface of a radiator blocked off from behind by mechanicals.

FormerE30Owner

By Increasing the pressure at the inlet of your ram device, you are simply reducing the air pumping loss of the engine slightly, not introducing more air. The very slight air pumping loss difference is not worth almost a 10% increase in mileage. At any rate, if more air is introduced, the computer adjusts the fuel accordingly and then modulates the engine speed to give the speed that you want, i,e, the same horsepower is produced to give you the same speed, albeit at a very slight loss in air pumping loss. Even then, the extra length of pipe introduced will reduce the pressure back to the original pressure at the original inlet at the filter box, hence , no gain.

Also, the only proper way to calculate mileage is to use fuel consumed with miles traveled. The on board computer has too much variability and lack of repeatability to be used as a statistical tool. Unless you calculated your mileage properly before and after the change, then I find your claims suspect.

Respectfully,

Bob P.