I've searched a while, but haven't been able to come up with much good data on the horsepower and noise gains with just secondary cat removal. According to some very knowledgeable people, there is 8-10 hp to be gained from the removal. A big advantage is you don't have to worry about the oxygen sensor, and it's easily reversable.
From what I've seen on the search, there is not a significant increase in the noise, but there is some. Does anyone have input on how much performance increase you would see just from the secondary cat removal alone?
So, minimal gain with just section1&2, I believe most of air restriction is on the OEM header/precat.
From noise level, IMO, justsection1&2 alone sound so stock with a little raspy at the higher rpm, but magnitude will increase dramatically with aftermarket muffler.
So, minimal gain with just section1&2, I believe most of air restriction is on the OEM header/precat.
From noise level, IMO, justsection1&2 alone sound so stock with a little raspy at the higher rpm, but magnitude will increase dramatically with aftermarket muffler.
Thanks - I hadn't caught that one. Looks like without the dip at 7500 rpm the gain would have been in the 5-10 hp range. Nice torque gains as well. For the minimal price, I'm seriously considering that mod.
nope the x pipe replaces the resonators just before the muffler's !! the secondary cats are the pipe in front of the xpipe just before the primary cats !!
as a matter of fact just yesterday i spent 4 hrs removing my ss race and x pipe and installing eis sec 1 sec cat delete eis sec 2 eis x pipe and eis sec 3 sport mufflers !!
so my initiial impressions were that even with all 3 the system is still fairly quiet like 40% louder than stock not even close to eis race by itself !! inside the cabin there's defenetly more v10 noise esp under the front seats , i like it !! and finally i really didnt notice any negligable power changes although it did feel like it was flowing alot better like he power was smoother or something !!
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