(BusaCruise @ Apr. 07 2007,19:51)
(JINKSTER @ Apr. 07 2007,14:55) Sorry...i just can't buy that theory...i usta work for Pratt & Whitneys large military jet engine R&R/Test Facilty in West Palm Beach, Fl...twice...each time for just under 5 years..and?..had a hand in building lotsa "Flow Rigs" so engineers could test airflow before putting it into actual application and as i understand it?..pressure or vacuum in a sealed contained area doesn't vary from area to area...will there be a "ZONE" where it rapidly decreases at WOT right at the intake mouths of the demanding T-Bodies?....yes...but 99% of the rest of the airboxes internal area will be under an extremely consistant pressure or vacuum level..whatever the case may be..heck..following that train of thought?...is like saying that the air pressure in your tire is greater at the top than it is at the bottom when you're letting air out of the stem....and i just can't buy that..pressure and/or vacumm doesn't vary in a contained area...and?..
Then that "TEST" is null and void if the equipment wasn't up to snuff with the engines operating parameters...alls it proved is they didn't have the appropriate test equipment to be capable of yeilding accurate results right at the most important part of the test...high-end max rpms.
I still think this is worth investigating..i've also spoken with Ken Wheeler (Wheelers Performance) and he claims that the ram-air intake openings simply aren't large enough..which is why a "Small Airbox Mod" really doesn't make sense....amybe for low-mid range torque but not for top-end speed runs..because the AMOUNT of volume that's under pressure is critical to benefiting ram-aire as well....gents?....we may very well need a completely redesigned airbox..one of massively increased volume...JMHO and L8R, Bill.
first of all....my apoligies to anyone that has read my other statement about the air entering the upper half of the box....
the air in fact enters the bottom compartment of the airbox (if you have an OEM style airbox) and then has to be deflected upwards...flow from the center of the air filter outwards and then do a near u-turn to get to the TBs.
Not exactly efficient...but functional
now...unless you worked on a flow rig designed to test our airboxes, you are comparing figs and twigs.
the pressure affects can be different because of the way ours are chambered.
Take a look at the hondas and kawis... many of theirs have a direct "line of sight" (generally) type path from the intake tubes to the TB intakes.
I think Suzuki was more worried about the volume of air it could provide, opposed to the charging effect they could deliver.
and nothing about our systems is even remotely sealed...
(don't forget the drain holes built into the box and that stupid foam...lol )
if tires were equipped with different chambers...then they too could have the potential for more or less pressure in those partitions.
as for the "test" mentioned....the hardware used functioned just fine for every other machine in the group ... it's just that in part...the design of the Busa airbox was unable to provide a positive pressure similar to the other bikes, which led it to a "less than ideal" test result.
it still made power...just not the increases seen in the others.
whether it be by intake tube design or airbox design...you still aren't going to create any pressure that would make a hoot's bit of difference to the crankcase breather tube.
here's a snippet from one article...
SUZUKI GSX 1300R HAYABUSA: Here was our first revelation: Going 190 mph doesn't necessarily mean airbox pressure will be sky-high. Note that the pressure stays below ambient until the Hayabusa reaches 145 mph! It finally peaks at 16mb, but the pressure fluctuates heavily getting there, due to the big 1298cc motor gulping down huge quantities of air. The Hayabusa's cylinder head flows a tremendous amount of air, demonstrated by the motor's incredible 160-horsepower output.
