The single Eram unit gained me 9 HP peak and a ton down low back when my SE was pretty much stock other than a KKM and home made stainless steel CAI. Dyno proven in front of countless CEG'ers. Outran a few SVT's the same day at the K.C. CEG Nats in '99 too. :p
The difference in using a Y vs inline for the super eram is total CFM of the engine. Larger, high revving engines may prefer the Y pipe set up, but most engines post better gains with the inline config. I would have more of them if I didn't have other things planned at the moment.
