Hey Oscar, I like that physics! You guys have answered my questions on ram air for my header tank. I bought a fiberglass tank with ram air in the cap and 1/4 inch fitting near the top. I changed the 1/4 inch to 3/8ths got rid of the ram in the cap and am running 3/8 tub to a collator, and then a 1/4 to an Aerocarb which only had a 1/4 inch inlet. Just as an aside, the tank was contaminated with some kind of tar and I had to open it up and clean it. This is probably not interesting, but my 2 bits. The chatter on air locks was good too and I am going to try to get all my tubes straight. Larry Bell
On Tue, Apr 8, 2014 at 10:06 PM, Oscar Zuniga <taildrags at hotmail.com> wrote: > Joe wrote- > >I have no data to compare as it was built like this from the get go > >but I do know that my fuel pressure from the header tank (gravity feed) > >has never been below 8/10 of a pound even though mathematically > >that should be impossible given the height of the tank at low fuel level > >above the pressure sensor. > > Joe; how did you figure the math? With, or without, ram air pressure? To > get 0.8 psi by gravity head alone, the difference in elevation between the > static fuel level in the header tank and the place where you measure fuel > pressure (presumed to be the inlet to the float bowl) would need to be a > little over 22" depending on what fuel you're running and its specific > gravity. That's a law of physics that can't be altered unless you are on > another planet where the force of gravity is different, or if you are > somewhere near Groom Lake in Area 51, and all bets are off. However, if > you were referring to your static head *plus* ram air pressure at cruise, > it's not a stretch because (example): at 124 MPH, the stagnation (ram) > pressure of air at STP is about 0.3 psig, so your gravity head of another > 0.5 psig would be an elevation difference of a little less than 14" between > static fuel level in the header tank and the inlet to the float bowl. > Probably not unrealistic for your setup. > > Whatever the case, you've seen 0.8 psi at the carb with your setup, and > there is no arguing with that. Good info. > > Oscar Zuniga > Medford, OR > > _______________________________________________ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options >
