I read on here somewhere that some tuning issues with the lunchbox are bc of the lack of vaccume because of the missing airbox...
Anyone ever thought of adding 2 inches or so of pvc between the lunchbox and carbs?
Maybe test with pvc legnth and such to get the right amount of vac, so you have a free flowing intake, and the vaccume too?
Now remember, I have a GR, not a GS. But my intake is as follows - BS36 carbs, the original airbox boots like these:
http://www.ebay.com/itm/1983-Suzuki-GR650-GR-650-X-Tempter-Rear-Carburetor-Carb-Boots-/250919660717?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item3a6bfa2cad
A couple small sections of PVC (solid area for clamps), and then the K&N. Works great for me.