Cmon now...thats not a fair comparisin (as if anything is). But an optomized y with stock 60k mile cat vs a sho y pipe with a NEW high flow cat. Thats comparing a car on wheels to another w/out. 10 HP is a nice gain too, but consider if your cat was clogged or crap before hand if it was robbing power from you...you could say a new cat got you up to par (where you should be) and the y pipe only gave you 5-6HP. I'm not saying all this applies to you, but its a lot more than this vs this.
