I'm pretty sure those are VERY old AA systems, or possibly just tanks mounted on new regs. There is one at my shop that is brushed aluminum, and sounds similar to what you are describing.
PCIII Custom Sato Banzai map, Scott's Stearing Damper
Sato Banzai's ,2CT's with 190/55 rear
Gilles Rear sets, CRG levers
HID's High/Low, 520 15/42 with Xring
Speedo healer, Corbin seat
"RC51's are not for everyone...not everyone likes twins messing around between their legs"